What Causes Elevated Heart Rate With Sharp Pain In Chest While Breathing?

I m a 29 year old female,111 pounds. My blood pressure will spike and I feel my heart pounding.Sometimes I feel a sharp pain when I inhale. The other day i was at 164/98 and heart rate of 120. But every time I go to the ER they make me wait so long before doing the EKG. By the time they check it lowers.Not sure what I should do.