Hi I Think I Have AUTI, Certainly An Infection But

Hi i think I have aUTI, certainly an infection but my GP only gave me 6 tablets, now burning and stinging have started up again. i have some expired trimethoprim 6 months expired can i still use it as this is keeping me awake, I also have some clarithromycin but I don't think this is any good for UTI's. thank you.Sorry forget question I had no idea this was going to cost.