46-year-old 'millennial therapist': 7 things I regret not doing in my 20s and 30s

When I first started my career as a therapist 10 years ago, I didn't expect to be working almost exclusively with millennials. But for the past five years, I've sat across from hundreds of them and listened to their struggles, fears and triumphs.

The opportunity to work with young adults has been a gift because it has allowed me to reflect on areas of my own life — and pass along the advice I wish I had received when I was their age.

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Every once in a while, we all need to look back at our lives and think about what we could have done differently. At 46, I still have a lot to learn, but I hope the wisdom I've gained along the way can inspire you to make positive changes in your own lives.

Here are seven things I regret not doing in my 20s and 30s:

Financial experts have noted that not saving for retirement is one of the biggest money mistakes millennials make. And, according to a recent survey, nearly 60% of adults admitted that neglecting to save is No. 1 on their list of regrets.

That's something I can relate to. In my early 20s, the idea that I would one day grow old and retire never fully sank in. I'd often spend entire paychecks on things I didn't need. I thought I had all the time in the world to start saving my money.

It wasn't until years later, when I learned money basics such as the power of compound interest or the importance of contributing to a 401(k), that I finally buckled up and got my finances together.

Now that I'm in my mid-40s, having financial security sounds a lot more appealing than fancy cocktails and designer brand clothes.

At 24, I packed my backs and moved to Los Angeles to pursue my dreams of making it big in Hollywood. While I was grateful to have a job, I regret not having the courage to stand up for myself.

When I was denied a raise, I didn't ask what it would take to get one. When I felt mistreated by a superior, I kept my mouth shut because I thought speaking up would hurt my career path.

Starting a new career in your 20s can be intimidating, but standing up for yourself and calling out poorly-handled situations can help you thrive in your career — while also inspiring change in your workplace.

If I could go back in time, I'd tell younger self: You may not have years of experience, but you do have the right to ask for what you want and need in order to find meaning and joy in your work.

I was so focused on my career in my early 20s that I failed to spend time with people I loved and cared about most. I assumed I could always show my appreciation for them "later."

But something horrible happened the year I turned 27: A close friend passed away — and suddenly, "later" no longer existed. Instead, there was only grief and guilt.

If only I had taken the time to say those five words: "I am grateful for you."

Now, I express my love and gratitude more frequently, and I encourage everyone to do the same. Whether it's a friend, romantic partner, parent or even a mentor, failing to express gratitude and love for them is often a major regret for most people.

Being 28, broke and jobless was a painful experience. I felt like my entire identity had been torn away. I'd held onto my Hollywood dream for so long that I didn't know who I was without it. It felt like all of my friends had it figured out. They had great jobs, great relationship, great plans. They were happy.

Meanwhile, I was lost and back at square one.

But we all move at different paces in life. Patients in their 20s often tell me, "I'm turning 30 in [X] years and I don't have a successful career." For some reason, we've assigned "30" as the age in which we must have our dream job — and if we don't, we feel as if we somehow failed along the way.

Here's my advice: Don't waste time obsessing over where you think you should be in your career. By slowing down and embracing your journey, you'll learn a lot about yourself and what you really want to do with your life.

After realizing that Hollywood wasn't for me, I needed to consider other options. My father and sister were both attorneys, so I tried doing some trial consulting — which I didn't enjoy all that much.

Deep down, I really wanted to be a therapist. I often thought about starting my own practice, but kept finding excuses not to do it — all because I didn't have enough faith in my abilities. (Of course, I eventually got over my insecurities and made the jump. I'm happy I did it, but I wish I had done it much sooner.)

Now, when a patient of mine expresses doubt, I encourage them to take risks. I remind them that even if they fail, they'd fail knowing that they weren't afraid to try.

Health brings a type of freedom and happiness that very few realize — until they no longer have it. When you're young, it's easy to take your health for granted.

It wasn't until I was in my early 30s, when my father was diagnosed with cancer, that I started to make big changes in my lifestyle. But I regret that it took seeing my family suffer in order for me to focus on my own health.

So many people say, "I don't have time to go to the gym," or "I want to eat what I want to eat — who cares if I die early?"

But ask any doctor and they'll tell you: "It's not about dying sooner. It's a matter of whether you want to be stuck with a chronic disease and suffer for 10 or 15 years while modern medicine tries to keep you alive."

When I first started working as a counselor at a rehab center, many of my patients didn't like me; they were angry at me for enforcing rules and for challenging them.

But their anger had very little to do with me. More often than not, I'd be the only person in front of them, so I'd get the wrath of their frustrations.

You can only control things like what you create, what you say, how you feel and what you think. But you can't control how someone else might receive all those things.

With this essay, for example, I'm in control of how honest and vulnerable I am in sharing parts of my life with you. But I can't control whether you find it helpful or not. My job is to show up and be my truest self. The rest is out of my hands.

Tess Brigham is a San Francisco-based psychotherapist and certified life coach. She has more than 10 years of experience in the field and primarily works with millennials and parents of millennials.

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