Well, it is hard to say for sure but am guessing that it is your body is just getting used to the hormones. Taking your pill religiously? Do the instructions say that you are safe the first month you take it? Some do say to wait for sex until after the first month (unprotected sex that is). See what the instructions are for the one you are taking. And if you feel funky or this continues, give the person who prescribed it a call for guidance. good luck