I have been on birth control for six years. I was on ortho-tri-cyclen lo up until about 6 months ago my doctor switched me over to Tri-Lo-Sprintec and I haven't had any problems until today. My period doesn't come until the fourth inactive pill, and that's been regular for me for the past six years. Today, my period came four days before the inactive pills. I've taken my pill religiously every day at 8pm this month and I didn't miss any. I did throw up on Saturday (10/1) about 6 hours after I took my pill. This has never happened to me, so I'm wondering if I have anything to be concerned about?