The day I am typing this question is my 5th day since I contracted the "stomach flu" (if you include the 1st day). I feel completely well now except my lower abdomen is in a lot of pain and I have a terrible headache. Also, every so often my head starts throbbing and pounding when I move my head or get up from a sitting or laying position. These are the only symptoms that have persisted to day 5 and I'm unsure if I should be concerned about either of them.