cramps, headaches, bloating, pregnant?

About three weeks ago i had nausea every night, to the point where it kept me up. My sense of smell became extreme, to where the smell of certain everyday foods made me nauseous. The nausea lasted for three weeks straight, then became kinda on and off..like i'll go a few days without it.
Now i have at times extreme gas which causes me to belch, and the feeling of being bloated. While im having this on set of gas, it's occompained by mild cramps that tend to make me nauseous. My lower abdomin can feel sore at times. An example would be that last night even laying on my stomach was uncomfortable. The mild cramps can come at any time. I can go from having diarrhea, to constipation with in a few days. Untill this month I might of had a headache once a year. To now being able to have three of them in one day. And that's been happen for about two weeks now.

I thought the gas and cramps was from something i ate, but when it happens it could be at times where i havent eaten yet. Like it might wake me up in the morning, or during the evening before dinner.

I thought maybe some of my symptoms ment im pregnant but now since the pains(cramps) here im thinking it could be something else. I also have been feeling like my periods about to come on for a lil over a week now. its not due till the 12th. My boobs are much fuller now too. Not to sore though, but i did by a new size bra. :-)

oh yea and me and my boyfriend have been having sex for a month and sum change now