regretting A level choices and basically everything ever

I've recently become really demotivated after doing TMUA and have started to realise that none of my subjects actually make me happy anymore, i wish i had taken english lit and RE or something similar but i chose to take maths fm physics and comp sci. I enjoy comp sci usually but i just feel like im not going to get anywhere with it because call the people around me that want to do this subject always seem to be so much smarter than me and idk what to do at this point. I feel like i would have really enjoyed studying literature or philosophy but i also feel like ive missed my chance now.
I was so optimistic when applying to cambridge comp sci but now i dont even know if im gonna get any of my offers, i wouldnt be opposed to a gap year and reapplying but i feel like being forced into a gap year is gna be so bad for my self esteem. i feel like all my effort is futile bcs ppl r so much smarter than me and theres js no point bcs ill never be the best at anything and i feel like thats all that STEM is; everyone just tries to be the best at it and if ur not ur worthless. what am i even meant to do atp bc i cant change my A level choices this late (im yr 13 rn). and then u hear abt ppl getting like 7 or 8 A levels and u js think to urself like what is even the point of this anymore when there r ppl like that bcs im never gna surpass them and everything i try to do theyd be able to do better and then theres no point pursuing smth u wna do bcs someone smarter is probably doing that and so why dont u js find smth rlly rlly niche that no one else is rlly interested (and tbh neither r u but at least ur the smartest to do it).
anyway i may js be spiralling a little bit rn idek it all js feels like a deadend rn