help!

Okay I don't know if this is normal or not because I lost my mum and I won't speak to my dad about this stuff so can someone help? Anyways so I get my period tomorrow & my nipples have been hurting since Thursday. I can't pinch them with out pain, I had sex  over a week ago with protection and he pulled out before he came. And I know that I couldn't be pregnant because I google all about it stressing but it's said my bra could be the wrong size or an infection and that people get it a week before there their periods.. Is the pain normal?