Hii, don't be discouraged! I was in a similar situation to you mid year 10, when I dropped to a 5 in physics as I hated it and neglected it in my revision. I decided to lock in even though I don't need physics, I didn't want it to bring my report down [plus sixth forms would prefer a well rounded student]. So I did a TON of past papers and truing to understand the concepts rather than memorise. The next set of examinations I got a grade 9 and I have not dropped since. Ironically the subject I hate[d] the most is now one of my best.
The moral of the story is that we still have some time to improve, don't avoid the subject, face it head on, if you get overwhelmed revise it in another way because I think in your case taking a break could lead to procrastination so if you are reading notes, maybe switch to a video or making flashcards. past papers are your best friend, you shouldn't memorise mark schemes but use them to understand what a certain question wants from you / wants you to talk about because you start to see a pattern. Also remember to learn topic specific vocabulary such as fusion, fission, red shift etc as you could say everything correctly but still not get the mark. Lastly look over your weakest topics and do practice papers on them to fill the blanks in your knowledge.
You are not a failure and you still have 3 months to get the grades you want, use it wisely, I don't want to sound harsh but if you spend your time worrying and getting in over your head instead of working you will really regret it because I trust you have the ability to do much better, don't mess with your own potential. I hope this helped lol 😭
~From a fellow medicine hopeful