2 missed periods

So I'm in a bit of a pickle... Last month I missed my period, so a week after I took a preg test and it was negative. I waited another week and still another negative test. It is now coming to the time where my next period is supposed to start and I don't feel anything. I've been off birth control for about 4 months . Since being off birth control I did have 2 periods. So idk if I should take another test.. Maybe do a blood one at the Drs? Not too sure. Anyone else ever have an issue like this?