rant about college

hiiii first sorry for bad english ,, okei im turning 20 in june and im studying medicine but rn im repeating the third semester because i didn't pass physiology,, soo idk ever since i was chosing what to study i didn't feel capable for that carrer and at that time i was between medicine and veterinary (and i know both are hard and kinda the same but no) but i was more biased for veterinary but even though i liked it and felt more "passion" for it i didn't choose it becuase i thought it would be even more difficult , ok so ever since I started medicine I feel like is not for me, honestly I just stayed because I passed the entrance examination (I didn't thought I would) but rn idk I don't see myself as a doctor for humans in the future but idk what to do because my mom already put so much money for my college and I feel so old to start something new but at the same time I don't wanna stay there,, soo can someone whose been through something like these share your experience pls