I went to the ER yesterday because of back pain and cramping they hooked me up and you could clearly…

I went to the ER yesterday because of back pain and cramping they hooked me up and you could clearly see I was having contractions but all the tests came back negative for preterm labor but they have no idea why my uterus was contracting! It makes me really mad that they have no idea and I only got one hour of sleep because of how uncomfortable this is!