HELP!

So I'm 30 days late on my period. But this is normal for me, as I have a severe case of PCOS. I took a pregnancy test 2 says ago & a week before, & they're negative. But I just went to pee, & when I went to wipe, I got this Charlie horse feeling in my right abdomen, & then a pop followed by a gushy bubbly feeling, & then the pain stopped.. But I still feel crampy.. Should I be worried?? Should I go to the ER??