Really need answers because I'm going crazy.

So I have a six month old and my periods came back when he was two months old. I had ovulation bleeding on November 16th which means I should have started my period on November 30th. I haven't started and I've taken 4-5 tests that are all negative. My doctors office said I have to wait until Wednesday before they will give me something to make my period start, but I need answers now. I have been feeling off for the past few days and I know that you can get false negatives if it is an ectopic pregnancy or if you are having multiples which I have a chance of because my mother is a twin. Any suggestions would be great on what to do.