How do I stop being extremely self conscious of my age?

Posting this because I really need help as this is genuinely making me depressed and hopeless

For context: I am 18 years old and I am nearing my 19th birthday, I am also medically disabled. Yet despite this, I can’t stop feeling as if my life is already over. I did manage to graduate school but I’ve never gotten a job, a drivers license nor have I lost my virginity.

There’s also the issue with expectations. I’ve been conditioned to believe teenagehood is the prime of life and that I should do everything before it ends: get into a relationship, have sex, become independent, get pregnant, etc. There’s also the extreme influx of teen videos on porn sites that further demonstrate this extreme narrow of being desirable as gross as it sounds. It doesn’t help my friends have already grown up and are becoming independent with one of them already being in a relationship with a 21 year old at 17, further showing that I’m lagging behind them.

I know this is an extremely unhealthy view to have, as much as I wish to stop it, my brain won’t let me change my views. I’d genuinely appreciate any advice from people no matter how small

Update: Thank you so much for everyone who decided to comment, I know my views are very rose-tinted but it was really helpful to have people share their experiences and tell me what i needed to hear. Also, I’m going to be checking up on my friend to see if she’s alright. Once again, thank you! ^{^}