going crazy

I am currently on cycle day 75 and no period. I've gone to the dr for blood work and thus afternoon I had an ultrasound and an internal exam. I'm waiting on the results of the ultrasound, but the blood work came back negative. my Dr is brushing my concerns aside and it's making me crazy. I just want everything to be fine so I can go back to ttc. no one ever told me it would be heartbreaking when ttc.