I have not seen my period for a month and I am not pregnant what can be the problem:(:confused: I took three pregnance test and theey all show negative

Well it is not uncommon to be late or miss a period altogether once in awhile.

Also, though, if you are having sex... there still runs the chance that you could be pregnant and your HCG levels just aren't high enough to register on a HPT.

I would suggest either waiting until next month and see if your period comes, or go to your doctor and get a blood pregnancy test to make sure.