I Take Lutera BC And Have For Over A Year.

I take Lutera BC and have for over a year. Never late on a pill (actually took two in one day because I thought I forgot to take it about 5-6 months ago), and had sex, he used a condom and didn't finish because he has problems keeping it up. About 5-6 days later I had severe nausea and puked for several hours (once every hour), no fever, had mild diarrhea. Went to a doctor and he said it was gastroenteritis. The next day I still puked and had nausea/diarrhea, also small headaches but may have been from lack of eating and fluids. I also had severe cramping like I was on my period, but this was a day or two after the initial puking and doctor's appointment. I won't get my period until the 14th of this month, so it's too early to take a test. Just worried and need some confirmation that I'm not pregnant.