Three And A Half Y.o. Girl With Not-yet Dx But

three and a half y.o. girl with not-yet dx but probable asthma threw a tantrum about getting ready for bed throwing self around on the floor and non-stop screaming. When Dad held her still (hand on her back) hoping to calm her, she stiffened up, urinated, and stopped the screaming all at once for aprox 20-30 seconds. Then she was up and acting normally and has been ever since (about 20 minutes). Parents are sure this was a seizure and are near panicked. Call to pediatrician's office got the "office not open" message. Does she need to be seen tonight or is she OK to wait for tomorrow?