Wierd period this month

I don't want to go out a buy a test again but I did at the $1 store last Saturday and it came up negative. Yet, this month my period was very peculiar. My periods usually lasts 5-7 days heavy the first and second day then medium flow and slowly it goes away by the sixth day.
Anyways, this month- period started on the right day and at the same time I got really bad stomach aches I thought it was due to gas but I took Pepto, tums, even gas x and it didn't go away for about a week! And I never get stomache cramps only in the lower region where the ovaries? Are but not high up on the top of my stomach. Well, on the 2nd day I was spotting almost a very light flow it was gone by the middle of the day. I didn't think too much of it until I started feeling nauseous and even had to run to the bathroom after a workout to gag. Hence the preggo test that followed. Negative. So I thought maybe it's just changing course but a week after I was spotting brown for half a day. That the flying eff. Boobs are really jiggly and sensitive but doesn't hurt starting to experience some cramping lately, hips and thighs and lower back aches, and nausea died down recently but occasionally Id get a small waves so perhaps it's all in my mind.  However today Which is now 2 weeks after the wierd period im highly sensitive. Bf was talking about our dog being sick and I was crying with all sorts of crazy thoughts. I swear I never get THAT. Emotional! I can't afford a doctor due to lack of health insurance. But could it be pregnancy or something worse or maybe I'm just being overly worried?