Shall I take up AS physics in year 13 if I'm interested in Nat Sci or Medicine?

Background: Currently taking Bio, Chem, Maths and English lit (finished my ASs in those 4), planning to apply to medicine or natural sciences (cannot decide yet because I love both these courses and am doing hospital work experience in August which I will use to decide), I am not planning to apply to uni in year 13, I do not feel confident that I've gotten good enough AS grades to apply and am still waffly about the course I want to do, but doing Medicine or Natural Sciences at Cambridge would be my ultimate dream, I've attended tons of masterclasses and I've just fell in love with the courses.
My question is, shall I drop A2 English Lit and pick AS physics? I love English Lit but it's obviously not got anything to do with my dream courses, but English Lit has improved my academic ability. I know that I will love physics, because I loved GCSE physics and am quite interested in physics in general. To what extent would having AS physics help my application (this is particularly for Cambridge) ?
Is better to have 4 A*s (hypothetically) in Bio, Chem, Maths and English lit OR 3A*s and an A in AS in Bio, chem, maths and physics?
I know this a very odd situation, but if anyone has any insight on anything please help out!

No, you have 3 sciences which is perfect for Cambridge, and 1 more than is required by all other medschools.

There's no point adding an AS.

What about for natural sciences? Thankyou so much for taking your time to reply!

Which modules would you want to study in NatSci? You can see the preferred/required A-levels...

https://www.undergraduate.study.cam.ac.uk/courses/natural-sciences/part1a

I'd like to take a chemistry route with maybe 1 or 2 bio related modules, would I largely struggle without some advanced physics knowledge? If I take a gap year I'm planning to teach myself some physics and further maths content, but would it be better if I have that AS level?

Nope, it's not required.

Okay thankyou, I'm sticking with English then! Thanks for your help