Pregnancy- To be or not to be that is my question

Patient: I am a 25 year old woman with an almost 4 year old daughter. My husband and I are trying to have another baby. My last menstrual period was 8-28-11. I used an ovulation test kit and my husband and I made love every single day over that week. I also started taking prenatal vitamins with DHA and folic acid (800 mcg)just to be on the safe side and prepared. I have been having nausea since a couple of days before I even ovulated and then a few days after ovulation I began vomiting. Then came the breast pain and swelling. The breast pain is intense at times and my left breast looks and feels more swollen than the right one. I tried to take a pregnancy test this morning and it was negative. The breast pain seems like it gets worse everyday. I feel like I’m having menstrual cramps but I’m not sure. Am I crazy? Isn’t it too soon to have symptoms?My breasts have never fealt like this before my period! They really hurt! And I am vomiting for no reason! Are the prenatals and folic acid making me sick? I did not have symptoms that early with my daughter. My period is not due until Sunday and I took a test today and it’s only Monday but the first response pregnancy test said it can detect it 6 days early. But I am confused because I fealt some cramping tonight accompanied by some really bad breast pain. I cannot wait any more. It’s driving me crazy. I really think I’m pregnant at moments and then other moments I kind of think I am not. My husband has also noticed the swelling in my breasts.