Test PLEASE HELP ME !!

Ja
I haven't been on my birth control since September 2016 and I missed my shot in December 2016 had sex January 10th and I still haven't came on my period , my last period was December 19-27 and I'm still not on !!! I just took a test and nothing came up what does that mean ?? And I still haven't came on my period yet ??? Should I be worried ??