Possibly pregnant with these symptoms?

My husband and I have been TTC for about a year now. He just got home from deployment, and we just got married recently, so we're ready for it. My latest cycle was from June 29 - July 3, which is kind of weird, because I usually have a full 7 day period. There was a lot of brown discharge, but there were also blood clots. What concerns me is that 3 days before my period I was having sharp pains in my lower abdomen, and I thought I was starting, but I started after them 3 days. I've been off of my period for 6 days now, and I still have mild menstrual like feeling cramps. I also have random sharp pains in different areas in my lower abdomen. I also have been slightly nauseaus, but not enough to make me throw up, and for the past two days everything I've ate has gave me heartburn, which I rarely ever get. I have a doctor's appointment on the 14th for my OBGYN, but I'd like a little input to know if I could possibly be pregnant. Has anyone ever experienced this in a pregnancy?