Amenorrhea?!

Can anyone give me anymore information about it ?
I think this is what I have I missed to periods all test are Negative and I keep cramping and hurting. Yesterday I had the serious runs. Gross I know and everytime I pre I get minor cramps on my right side. Then it subsides within two mins. I haven't had a period since the beginning of May and I stopped my birth control on May 11. 
Please help. I dunno what to do anymore.