I recently switched from the birth control patch to the pill. I have been on the pill now for 3 1/2 weeks (this is my spacer week), and I also started taking diet pills around the same time I started taking my birth control pills. I haven't gotten my period yet, and it is 3 days into my spacer week, BUT there was a really really light spot of pink on the toilet paper after I used the bathroom. Should I be concerned? I am not sure if diet pills effect birth control or now. HELP!