I was suppose to have my period on dec 18, I still havent gotten it & for the past 5 days I have been having stomach pains around my belly button, I am pretty sure its not my appendix. The pain comes & goes, but when its there its full blown. Sometimes the pain comes & I have to use the bathroom (diarrhea) but not very often. The pain hurts really bad & the longest it has lasted was 30 min, it also wakes me up at night. when i have the pains all I can do is not move so it doesnt hurt anymore.