Why do i feel sick to my stomach?

I notice when I take my aviane which is birthcontrol along with lexapro I don't feel good as if I didn't take them... has anyone encountered nausea side effects when taking aviane birth control? Could my body be reacting to not taking the birth control then taking it? I do skip pills sometimes when I work late and go to my boyfriends house or friends, but if that's the case he always uses protection. I want to know what's going on, these symptoms have been going on since last year. I talked to a doctor and they couldn't pinpoint what it was, my next aptt with my gyno is sometime in the beginning of june. Also keep in mind the dosage of my aviane is .10 mg which is extremely low for birth control but could it still be contributing to the symptoms??? What would you suggest I do.