Super Sick What could this be?

Trisha
First off I had my period 2 weeks ago I have already ovulated use opks. For the last couple days I am nauseous bad! I can't eat barely anything I am a smoker and if I smoke it makes me sick if I smell smoke it makes me sick. I don't want to hear smoking is bad I know smoking is bad and am trying to quit. I just want to know opinions. Thanks in advance