Irritable uterus?

Amber • SAHM to a beautiful, smart, energetic 2 year old boy and his newborn brother!!
I've been in labor and delivery for almost 5 hrs trying to get contractions stopped as I am only 28+3. They gave me a shot to stop the contractions and I am just waiting to be discharged now. The dr told me that I have an irritable uterus. Anyone have any information or experience with this?