What is considered morning sickness?

My nausea has grown worse the past few days. I had been having good aversions all along and slight queasiness. But now I've been feeling like I'm on the verge of puking...like severe nausea and gagging, but I can't seem to puke. Is it still considered ms if you don't puke? I always hear how ms is associated with healthier pregnancies and lower risk of miscarriage so I was wondering. Lol