My cycles are 34/35 days. My dec cycle was short 27 days so first day of my last cycle was Dec 30, 2020. Glow predicted my period day on 30th Jan, flow and Premom said 1st February. Today was CD36. I had cramps on and off for a week now , I though it’s my period but nothing until now. I checked on CD 34 with FMU using clear blue and it was negative . What’s going on ?? Doc said to wait until cd 40 for ultrasound to see why am having mild to moderate cramping.