How can I make my high school career more significant?

Hi! I'm currently a junior with a 3.8 unweighted, 4.0 weighted GPA, and a 1230 SAT score, with a class rank of 58/511. I've been stressing out for the past couple months because I feel like I don't stand out compared to my peers and in fact feel like I'm falling behind them. Many people I know have been taking countless AP's and honors classes since freshman year and a crazy amount of extracurriculars and I can't help but feel as if I ruined my future because I was too scared to sign up for more than one AP/honors class per year. For reference, my freshman year I took honors bio, sophomore year was honors english, this year (junior year), i'm taking AP psych, and because I was afraid of being behind, I signed up for AP gov/macro, AP bio, and AP english lit for senior year. In total, that would be 2 honors and 4 AP's that I'll be taking by the end of my senior year. My school has a little over 20 AP's, and I feel like I positioned myself up for failure because of my fear of failing in these classes. I'd really like to go pre-med while perhaps majoring in neuroscience, and have been considering colleges in California more near the coast (UCSB, UCSD, SDSU, UCI...), but don't know if I'll be able to with how my transcript is, especially with a lack of extracurriculars. I've done water polo for 3 years (planning to do it senior year too), volunteered at a child care service for a church, and helped with a family business, yet it doesn't seem to be enough. I plan to apply for an internship this summer with a medical-focus, and if I can't, plan to volunteer at the hospital during the summer. Does it even matter, am I too stressed out over it? My high school career feels so bland and average compared to everyone else's, is there something I could put more effort in to stand out more?