E.S.
I would contact the doctor's office and get a blood test done. I had 7 negative urine tests until I was 5.5 months along with twins and I only had that test done b/c I was going in for hand surgery and they tested me. I tested positive and the next week I went to the doctor's and they sent me for an ultrasound and sure enough, I was 5.5 months along with twin boys. I don't trust the over the counter tests now and my mom was the same way. If you have problems with them then don't hesitate to call your doctor and get a blood test. That's what insurance is for :o)