I've had unprotected sex with my bf around the middle of last month. We had protected sex since then. I've been havin sore nipples recently. I've taken a pregnancy test kit and it says negative. I had also taken a test around the beginning of this month and it was also negative.
Sore nipples can be cause by a number of things and are not a definitive sign of pregnancy. You should take a pregnancy test one week after your missed period date (if it does not arrive in that time) to make sure.