I have missed my period for the month of December. October and November I started on the 25th and ended on the 30th. I haven't had sex since July. I took a pregnancy test just to see what was going on, and of couse it was negative. I would be able to tell by now since I have a child. I've never completely missed a period before and I am concerned. What could be going on? Should I be worried?:confused: