scared and confused

I usually start my period around the first week of the month. last month and this month it's not happened. so I am 2 months late. I was in the emergency room on the 9th (2 weeks after I was supposed to start) because i was in so much pain that I was almost fainting and I was throwing up. they couldn't see anything on any tests. I took 2 at home tests prior that were negative and they did blood and urine and it came back that way too. I am not on a birth control that will lighten or stop my period, mine is prgesterone. a month before the symptoms my boyfriend and I were unprotected. is it possible I am pregnant or is something serious going on?