Im using the clear blue advanced digital opk and have gotten a "high" blinky smiley the last 3 days. I had an ultrasound and blood work today and the nurse said by my blood work she thought i would get a positive opk by tuesday. Just out of curiosity i tested and got a positive "peak" steady smiley. I was so excited i immediately ran to the store and bought more of the advanced digital tests and the clear blue easy test [with the 2 lines] about 45 mins- an hr after the initial positive test i tested again and recieved a negative on both tests and didn't even get another "high" blinky smiley. I don't know what to think. Anyone have an suggestions/advice?