Ugh morning sickness be OVER

I've had horrible morning sickness since 4w and I'm 16w now. Just this week it's started to let up (I am a teacher and have been on homemade diclegis and zofran) and I hadn't gotten sick since Sunday. Well this evening... I threw up everything I've eaten all day. What the hell?!  Severe morning sickness is miserable too of course, but this unpredictable random morning sickness phase sucks too. Argh.