So i went it for an ultrasound 4/30 to check on the cyst i supposibly had, i had sharp cramps weeks before but never around my period.

Ive been baby dancing for over 6 months, nd when she was going around she stopped (mind u i couldnt see whats going on, just glanced thru the tv screen) but look like she clicked on something and then a pulse popped up, is that a sign of pregnacy or is it my own heartbeat. I KNOW what my eyes seen like it was a pulse, i tested i believe weeks before and it was negative and had a period 03/18-03/24. What could this mean? Or am i eyes decieving me lol