What Is The Popping In Vagina Along With Cramps And Delayed Periods?

i have taken 4 pregnancy tests, the first three came back with a faint line the last one didn't come back with anything. i have been having cramps and now an annoying popping feeling in my vaginal area. i have not had any bleeding. i am 10 days late for my menstrual cycle. what could the popping and cramps be, could i be pregnant?