Help..

Brittney
I'm 17w5d and have been having pretty intense lower abdominal pain and some cramping, my whole body hurts now and I'm really nauseous. Went to the ER two days ago they told me I have a UTI, OBs office says I don't but if I don't get better to go back to a different ER. What can this be? Am I just over thinking all this? Any help would be great...