Hello,
It could be a combination of the "mini pill" and the alcohol causing the reaction. I would call your pharmacist and ask about certain side-effects and if this is possible. I know that some hormones (including the "pill" can cause headaches, especially if you already have an over-abundance of Estrogen in you, called "Estrogen Dominance" That, too, can cause headaches, so, like I said, ask the pharmacist and even your doctor.