Dealing with parent pressure???

I'm in year 13 about to apply for uni on ucas, i was originally going down the med/dent route but I decided it's not for me. My mum is super disappointed that I don't want to do that anymore and keeps telling me I'll regret it and makes negative comments about anything else I'm interested in. Then she says things like at least go for Oxbridge but my gcses were mid and I don't have the energy to prepare for another entrance test (I already did the ucat because she wanted me to, again, got a mid score)
I want to do biology or neuroscience but she keeps saying such negative things about it but biology is the only subject I actually enjoy and I realised that was the aspect I liked about med and dent, the actual technical and scientific side not being with patients, I am a MASSIVE introvert and not a people person at all. I've tried to tell her as well how I'm prioritising my mental health by going for something less competitive and have even said I'll apply to imperial or ucl to at least attempt at a top uni but she's just not happy - I should also mention she's Asian, studies at Oxford, and is now a professor so has high expectations for me, constantly saying I've got her brains and stuff but I'm very mediocre in academic and that's being realistic not deprecating or anything lol
Does anyone have any advise on how to get her to calm a bit or at least how to deal with it on my end? Anything is appreciated