Early-entry exams help??

Hi! I’m really confused and I realise it’s way too late to request that I take early-entry exams anyway (considering they’re next week), but I’d still like some clarity. It’s my own fault for not checking, but I assumed that they were for students hoping to study Medicine, whereas my desired degree is History. However, a few months ago my teacher recommended that I apply for Oxbridge (Oxford would be my preference), but due to the financial side and also anxiety that I’d struggle to deal with mock exams, a History assessment and the main summer exams, I pushed the idea away. So, I guess my question is: Do early-entry exams just apply to Medical students, can I still take them, and if not, does that mean I have no chance of getting into Oxford? I’m currently targeted A*AA btw. Thanks!