My bf went in unprotected

Yesterday, my bf and I were laying in bed when we started getting all touchy. He got up and went into the closet (I assumed he was getting condoms). He came back & went straight in. He didn’t finish because he started getting pains in his stomach. I turned on the light and saw he wasn’t wearing any protection. According to eve my fertile window doesn’t begin until 3 days.. should I be worried ?