Sore nipples??

Okay so about two weeks ago I had unprotected sex, he pulled out before the (ya know), but he still was nervous. Currently my nipples are ridiculously sore, and looking online it says either early pregnancy or just the bras I'm wearing, is this possible this early?? I'm too nervous right now. A lot of my friends told me that a male can cum without feeling it, which adds to my nerves. Someone help me out!