Echo at 12 weeks to jump

Hi! I'm new here and was wondering if anyone else has had an ultrasound around 14 days after ovulation! I feel pregnant but my tests are negative! They saw nothing in my uterus that looks like a pregnancy. But both ovaries were full of follicles and one was about to burst, even though I'm sure that was 2 weeks ago! I was supposed to get my period today but nothing yet, and I don't feel it coming either! Can someone help me!? I'm getting really unsure!! (We're trying for our second baby!) Best, Kristel