I Was supposed to get my period on the 15 of this month and have not yet. I have had these lingering headaches, nausea, certain smells bother me and there's things I can smell like candles that come out for Christmas and haven't been able to smell them. Also been very tired lately also. Took a dollar store test at 8 pm it was negative how long should I actually wait and when is a better time to take one