Helppp boob pain

So I just had a shower and my boobs are aching but only really when I touch them, I had sex last week and yesterday (protected both times using condom) and my period is due in 15 days. What do you think it could be? I can’t feel any lumps or abnormalities and I don’t usually have aching boobs before a period (PMS). I had been wearing a bra all day if that makes any difference? It’s kind of up to my armpit too, a cross between an ache and a sharp pain.