What Causes Fever, Nausea, Vomiting And Lack Of Appetite In Child?

4 days ago my 3 year old daughter had afever of 102 plus. The next day she presented with nausea and vomiting.we broke the fever but she still has a lack of appetite and continues to have cold hands and feet. I've also noticed her left eye is a little more read in the other. She seems to get better then goes back to feeling bad.should we let it take its course or should she be seen?