Regret deciding to do a resit ?

I have put in to do a resit paid etc but I now regret it .

It wont make any difference to my Uni application as its not in the subject I need to get into Uni and I have been too busy focussing on other exams.

Should I even bother ? Or will it look bad in some way..

If you have put on your Ucas application that you are resitting and you then do not take that exam, you have broken the terms of your offer, which is made on the basis that what you put in the application is what is going to happen. The university is within its rights to withdraw its offer as you have broken the terms of the contract. In practice, this is very unlikely to happen, but to cover yourself you must either contact the university and tell them, running the slight but real risk of them withdrawing the offer, or sit the exam regardless and not care what the result is. It's up to you.

I was definitely going to sit it ! I've paid for it after all. Its more the fact I will probably get a worse grade

They take your highest grade if you resit, so if you do worse than your first attempt then it wouldn't be counted. Don't worry