Late Period but Negative Pregnancy Test

OK my period are usually 22 to 24 day cycles every month. I have never missed a period unless I was pregnant. Late month my period came on the 14th and so for the Month of June my period was posed to come on between the 6-8 but as of today my period haven't came on. I've taken several pregnancy test and they all came back negative.. I'm so annoyed with all this..someone please help me on what I need to do.