Changing Uni course after 2nd year

Bit of a long one sorry guys... Basically I am just finishing my 2nd year of a 3 year Biology degree. The uni I go to is literally tiny (think high school) and so doesn't offer any other courses. I’ve hated my course and the uni since I started, ive essentially spent two years depressed and crying in my room. I have no idea what I want to do after uni, but I’ve been massively regretting not leaving the course and uni since the start. If i left I’d want to study physics, not sure what I want to do with that either which seems to be why people keep telling me to just stick it out cos ‘any degree is useful’. I cant stop thinking what if i had left, and now I'm thinking its too late but its really now or never the only thing i want to do after uni is go back and do physics somewhere else so i can have a good time and actually enjoy the subject but no way i would be able to fund that myself. The other issue is i have very bad A levels with 3Cs and no Maths so wherever i do physics id have to do a foundation year aswell. If i left now id have to self fund one year which is really not concerning me, in the other 3 years im sure i can save that amount. Its honestly been the worst two years of my life when it should have been the best and I have so many regrets of not leaving, I knew it wasn't right from the start. To make matters worse I took two gap years before uni so I'm now 22 so I wouldn't graduate until I'm 26 😕 would it be better to just finish my degree and suck it up that uni just wasn't a good experience for me then not use my degree or should i change while i can still get some funding, but then I’d be a fresher at 22.