I completely missed my last birth control pill last month, but started my next pack a day early so I wouldn t go more than seven days without the hormones. On the last day of the placebo pills I had unprotected sex. Then I got a prescription for Cephalexin (because of strep throat). I have had about 8 days of light brown spotting and then today it was dark brown. Expecting my period in 1-2 days. Last month was very light. What is the deal?