Is there any way to stop yourself from throwing up??? help

So I woke up feeling a bit strange this morning, super tired and not that hungry. Anyway, I went on with my day, ate some food (and I was fine) but I was just relaxing on the couch a few minutes ago and I felt like I was gonna throw up all the sudden. I felt weak, and it just felt like something was gonna come up. I don't know how to describe it. I haven't thrown up in YEARS and I'm extremely afraid of it, so I'm having a panic attack right now. I don't know if I'm actually going to throw up because I feel fine aside from feeling really tired and a bit nauseous but I'm terrified. Is there any tricks to stop yourself from throwing up?? :(