I had a normal period in April but when may came around it was abnormal... I wasn't bleeding heavy... it was lighter than usual and normally I have to use super tampons but this time I only used regular which did not fill up completely. I do take birth control pills but I believe that one did not work properly in April. I took a pregnancy test in may after my "period" ended but it was negative. Today my period was due and I haven't seen any sign of it... im moody... I cry over little things like watching some TV shows... slight headaches... feelings of becoming nautious without throwing up... nothing else really. Should I be concerned?

Although, you should not be overly concerned about pregnancy; you should always be concerned when you feel you body is not functioning normally. I would first take a pregnancy test. After you test tell your doctor about your symptoms and he will be able to give you a clear explanation as to why you are feeling so moody and ill. It could be any thing from depression to low blood sugar levels.