Suggest Treatment For Abdominal Pain And Back Pain

I am a 23 year old female, 5'8", 135lbs with a history of endometriosis and occasional temporal lobe seizures. Not pregnant according to pregnancy tests.. I have had some new issues. Cramping abdominal pain while urinating, then it goes away when I'm finished. Also, when I start walking fast or running, I have a very lower back pain that kind of feels like it jiggles up and down when I run. Very unusual for me. almost like my intestines are going to fall out or something. and also a bit nauseous on and off,and major change in appetite. Also, I have been frequently losing vision while moving from sitting to standing or crouching to standing. not sure if relevant. Should I see a doctor, go to ER?