Scared!! TMI

Okay so me and this guy we are friends with benefits and we have had sex several times and I’m supposed to get my period in 2 days and we used a condom but I’m pretty sure I felt him cum in me like honestly bc I think the condom came off and he normally pulls out but I felt it go inside me but I feel really sick and nauseous and have been and I’m staying very tired and weak and I’m sensitive to smells and I’m scared because I’m only 15

UPDATE: so basically my period is 2 days late and I’ve been feeling sick and I’ve been craving everyhting but I also have endometriosis and PCOS so it could be a cyst trying to burst but idk and the guy I had sex with. We got into a fight and we are no longer speaking.