Suggest Treatment For Dull Pain In The Pelvic And Hip Region

I have a dull pain on my right side near my hip bone and pelvis with a somewhat sharp pain that wraps around to my right lower back area. When I move the pain gets sharper. I seem to feel colder than I normally do, but don't think I'm running a fever. Earlier today I vomited once and had diarrhea, but now only feel slightly nauseous. What could this be? Should I go to the ER?