pregnant?

September 2nd I had unprotected sex a couple hours later I got plan b. (Symptoms of plan b headache & abdominal pain) about 4-5 days later I started spotting it was light but mainly brown blood lasted 6-7 days. About a week into taking it I stared getting bad back and neck pain and diarrhea. 2 weeks after taking it I started getting sore breast and all these symptoms are continuing. The cramps are not like period cramps they feel different. Does anyone have an idea of what it could be other then saying take a test after your missed period