Not getting period

Hello-

I was using the Nuvaring for a couple of months but quit back in October. Before that, I had unprotected sex in July when my relationship ended and protected sex the few times I had it after that. I have not had sex at all since then. I had my period in Nov, Dec and around New Years. I haven't had one since then. I have had some period type symptoms but no period. Negative pregnancy test. Not sure what's going on.