Methergine to stop bleeding

Does anyone here have experience with taking Methergine? I had a D&C two weeks ago to remove placenta left behind after giving birth (full term) and because I’m still having issues and bleeding so excessively, my doctor prescribed Methergine (3x day for 3 days) to cause my uterus to contract and hopefully stop the bleeding all together.

I took the first dose around 8 pm tonight thinking I would be able to sleep through it but I was clearly wrong. I just want to know if it gets better as you continue to take it? Anyone? I cannot do this for 3 days.