morning sickness question

Can someone please explain what morning sickness is like? I never had it with my 1st but yesterday morning while I was getting dressed for work...I had a wave of nausea come over me and dry heaved for a few minutes and then I was fine!! I also feel nauseous at night!! Could it be morning sickness...I know it doesn't literally just have to be in the morning! Lol thanks y'all!!