Someone up-thread mentioned a cough that nearly makes you sick. Our family have all had that over the last few months, with one actually being sick with the cough.
In our case, other symptoms included it starting like a cold, thinking we were improving after a couple of days, then really taking a down-turn.
Loss of appetite and dulled taste-buds lasted ages. Fatigue, weakness, and several other things!
It was unpleasant and long-lasting, but didn't really resemble flu as I know it.
I'm not sure there is anything that can be done other than let it run its course, rest as much as you can, and generally try to eat well and look after yourself.