cuts on vagina

my boyfriend and i broke up about a month ago. before that we had only been with each other (we lost our virginity to each other) and since then i’ve had sex with 3 other guys and done bits with one more. i’ve not had sex in about two weeks but for a while now i’ve had pain when i pee and sometimes a burning feeling in my vagina that normally goes away when i drink A LOT of water. i’m booked in to be tested on the 7th just in case but i assumed it would just be a UTI. for all boys i didn’t have sex with condoms (stupid but they were all friends and people i knew so i trusted them when i asked about STD’s). however i’ve just gone to pee and when i wiped there was blood on the tissue and still blood around the third wipe (it wasn’t period blood it was actual blood and we can obvs tell the difference lol). it does feel like there’s a constant burning but i put it down to tight pants since i’ve been on quite a few nights out and not letting my vagina breathe since i can’t take my pants off at home because i have a tattoo my mum doesn’t know about (no shorts only tight pyjamas). is this a sign of an STD?? or something else?? i’m so scared and i feel so stupid but please help (no hate please) 💛💛💛