Picky eater - or getting sick?

It is probably nothing serious. She may just have an upset stomach, or could be constipated, or just generally not feeling 100%. All animals (cats in particular) will instinctively fast or eat very little food if they are not feeling well. They will at times eat certain things to make them purge (thus her vomiting), and then eat nothing or very little until whatever is making them feel uncomfortable goes away. As long as she continues to drink water and doesn't lose alot of weight, she is probably fine. :)