i have been on the pill, just had my period july 2nd. It was a regular period, as always, but then i stopped taking the pill for 3 weeks. I am back on the pill and have been for 2 weeks. I have not yet started my period, and always have one every month. I have had all the signs of starting, cramps and all but no period, and have taken 2 pregnancy tests that were negative. Please help