ITCHY RED BUMPS

these bumps have been appearing around my inner thigh and butt...VERY itchy....I've only had sex once, we both lost our virginity at the same time...ANY IDEA WHAT THIS IS??? it's also been a bit itchy surrounding my vagina, the bumps are around there but not this badly...im only 15 and kinda afraid to tell my mom,i really need someone's opinion on what his could be...is there any way that this is an std or sti even if we were both virgins? HELP