Question for frequent flyers. I'm scared to fly!?

I've flown many times in the past, but I haven't in about 7 or 8 years and I've developed a fear to fly out of nowhere. I'm flying from Minneapolis to Phoenix in November for a wedding and I'm afraid of having bad turbulence. My mom told me a story about how she was on a flight that had it so bad that a few people were actually throwing up in the barf bags. I cannot handle being around people when they get sick and I hate throwing up so bad. Now I'm all worried about flying. Does anyone have some reuring words for me? And does anyone know what a flight is like from northern North America to southern North America in the fall time? Thanks!