Please read and comment ASAP

My boyfriend and I had sex a little over a week ago and I read that usually u can start feeling symptoms 10-14 days after. We always use protection and he pulls out even with the condom for extra caution, we also never have sex when I’m ovulating. Last night and this morning I was getting cramps and I woke up and my back hurt I’m a week away from my period. I figured the cramps are jus from bc I was constipated for almost two days and my back hurt Bc I slept on a hard couch maybe in a weird position. I get paranoid extremely easily. I am worried the cramps and back pain are form implantation. I am extremely paranoid can someone please help