Vagina Pain, & idk whats going on or what to do?

So okay, I started my period 3 days before I was supposed to ( i take birth control pills) & there was only 3 pills left til my sugar pill week. But i was like okay, this happens sometimes, whatever.

After a couple of days I thought “Oh yay! Im off my period, i wanna have a good time with my boyfriend.” & after the day goes by i feel fine, then i went to the bathroom after getting home & theres blood everywhere & so i get a tampon. After 30 mins or so, theres this pain literally in my vagina & around it like its sore ? & Idk what to do? ?????? HELP ???????!???