Here's the thing. The contraceptive free night two days after the last day of my period (which was around February 16th) wasn't a concern either because I was under the impression that I wasn't ovulating then. Well, I looked it up later on the internet and found out apparently it is entirely possible to conceive right after a period. In the beginning of this, this wasn't something I was going to stress myself out about. But then March 9th came and went. I'm now four days late, and I don't know what to do. Usually my breasts swell a little bit before I start my period, but they have completely MUTATED into these giant orbs and my nipples are causing me complete agony. Not to be gross or anything, but it's like I have permanently hard nipples. (which is not the case normally) So here are the symptoms: swollen breasts and VERY tender nipples, headaches, occasional cramps that feel like menstrual cramps, feeling a little nauseous but mostly at night, feeling very hormonal, and frequent urination. Anyway, I've taken numerous hpt's and they all come back negative. I don't know what to do and my period is nowhere in sight. Is it possible that I could be pregnant, but the tests are wrong?