paranoid?

ok i’ve only had protected sex, nothing ever happened w the condom, but i had brown discharge? i think it’s probably a cut or something because i was bleeding after sex and then the next day i had brown discharge. but i’ve has a weird discharge ever since and i just hope i’m not pregnant. i’m pretty sure i’m not, i’m leaning more towards and STI, because neither of us have had another partner, we were each other’s firsts so i think it’s a yeast infection or and STI, but i’m not sure how because i’m super clean down there, you know what i mean? i haven’t missed my period, it’s 10 days away