Am I pregnant? Or is this a uti?

My husband and I had unprotected sex June 11, 2011. After a week I've been having to pee a lot. I wale up in the middle of the night to go to the bathroom. I pee like 8 times a day. And it also hurts to pee but not a lot comes put. I've also have been feeling sick after I eat and late at night. I've been having headaches and moody. I was fine all day and happy and I was on the phone with my husband started balling. I have lower stomach pains too and my back hurts. I'd like to know if this is a uti or the beginning of a pregnancy.