Ethinyl estradiol / levonorgestrel
"So this was the first birth control I had taken and everything was fine the first three days, on the fourth day I randomly got sick, like hot flashes, lightheadedness, headaches, and vomiting, but after an hour and a half it went away. However from that day on I always felt a bit off and had lightheadedness and headaches for an hour or so every day always at a different time even though I took my pill at the same time every day. My period came early and I have never experienced such extreme cramping before. The only plus is that it didn't kill my sex drive and I didn't get pregnant"