Cramping before period is due. Anyone have any ideas?

I'm going to try and be as brief as I possibly can.

December 1st I had sex (protection- condom only). I started my period on December 2nd. My period usually lasts 7 days but ended on December 6th. Exactly two weeks after having sex and 9 days after my period came to an end, I experienced dark brown spotting for 3 days accompanied with some very mild cramps (definitely not period-like cramping). Two days after the spotting ended, I noticed some more spotting when I wiped then nothing for the rest of the month. Since then, my taste and smell have sky rocketed. Certain smells bother me and certain foods I used to like taste terrible. I've also been dealing with random waves of nausea ranging from mild to almost flu-like but I never actually get sick. I'm also extremely tired through out the day, to the point where I have to take 3 naps in order to not feel like a zombie. I thought maybe these weird symptoms were premenstrual related but I'm not entirely sure. It's now a new month and I am expecting my period any day now. Usually a couple days before my period is due I get horrible, debilitating migraines. So far, nothing. I'm also experience a new, random symptom of period-like cramping. I have never had cramps like this before getting a period so I'm a little freaked out. I feel like I'm going to get my period any minute and keep going to the bathroom to check but so far, nothing. I'm wondering if I should wait these next couple days for a period or if I should test for pregnancy now. Any advice? Has any else experienced this? If so, did you end up pregnant or not? Thanks. :)