if its proper flu you wont be working for at least 5 or 6 days mate.
have you got a high temperature?constant headache?,sore joints?,aching muscles?,chills?,sore throat?,bad chest?,runny nose?zero energy? and when you wake up in the morning a soaking wet bed because you ve been sweating so much?if you ve got all these symptoms then you ve got proper flu.
dont try and work or do any exercise or you can damage your heart muscles
i had it 2 weeks ago and i couldnt work for 5 days.still got a chest infection but its clearing up now.