white on the tongue with swelling could be thrush - a yeast infection. Your doctor should be able to tell just by looking. If you have recently taken antibiotics, this is even more likely. Your doctor will want to do blood work. Flu-like symptoms would not come from eating something bad, but rather you may have been exposed to someone ill at the resturant. Food exposures generally cause gi symptoms of vomiting or diarrhea and cramps. If you
were generally achy and fatiqued or any respiratory symptoms then it was not the food. If by flu-like you mean diarrhea, then it is possible that an ingredient you are not used to set you off or the way it was prepared. Food poisoning makes you very ill. Fever, vomiting, diarrhea accompany this.
DrStephanie