I advise against graduating at age 16 for several reasons.
First, when you get to college you’re playing for keeps. The frosh around you will be 18 and some may even be 19 if their parents red-shirted them in 1st grade. There is a lot of personal and intellectual growth that happens between ages 16 and 18+. Being 15 now it may be hard to envision but if you talk with older siblings of your friends and ask if they were equally capable at ages 16 and 18 the answers will be no.
As a prospective pre-med you aren’t just taking classes, you need to participate in activities like shadowing, volunteer work, perhaps lab work. Some hospitals and labs for liability reasons won’t allow those under age 18. Overall at age 16 there simply won’t be the same set of opportunities, nor will you be as able to handle them as you’d be at 18, no matter how precocious you are.
Beyond academics, college is about maturing alongside a peer group. Being 16 can create a noticeable social barrier with older students (half of which at college are over 20), and you may feel left out once your friends reach the legal drinking age and move their social gatherings to local pubs
I’d also say there are tangible signs your push to get thru HS is already causing problems. In the thread How much do B's impact ur chances at top universities? you wrote your math grades have been (100→98→92→90) meaning that as the difficulty ramps up you’re still doing well but not as well as you were earlier. Rather than taking difficult and important classes in summer school in a rush to get out of HS you’re better off taking them during the regular academic year IMO.
Lastly there’s your focus on either Ivy (as per your thread Can i get into an ivy league without being top 10%) or the fine schools you mention at the top of this post. If you really know you want to go into medicine you may wish to be more strategic about your college choice, consciously selecting a good place where you’d be among the top students rather than schools where everyone else is a superstar too.