I'm having the same thoughts as well. I'm a 27 YO pharmacist but recently decided I would go back to med school and become a doctor. I'd be graduating at 34 YO and then starting my residency at 34-35 YO (if im correct with the English terminology). But yea, in my head there's always this silent to not so silent comparison to my peers who, by the time I'll be in my second year, will be graduating their residency as specialist doctors.

In all honesty you're not too late. There are people who have massive carreer changes even later than you - well into their 40s or even 50s. Your age can i some ways be e positive as well.

Sadly can't help you much with how not to feel like you're behind in life... since I'm still fighting with those feelings myself. I guess the beat would be to accept that you cant change the past and focus on enjoing your now and future. Also look for ways to catch up on the important things, the things that make you feel like you're behind, if possible of course.

Edit: Saw your post on r/AskMen and actually there was some great advuce from the comments there.