DearCustomerbr /> This may indicate urinary tract infection. An infection in the urinary tract can cause pain in flank or one side of lower back. An infection such as this may also cause systemic symptoms like vomiting and clammy skin. These symptoms may or may not be associated with a raised or lowered temperature, urinary symptoms, abdominal pain etc. He needs to see a doctor as soon as possible to get himself examined and investigated. A clammy skin may indicate shock which needs urgent treatment and therefore urgent care should be sought.
He has started feeling better and the pain has subsided, he isn't clammy anymore
Is it ok for him to sleep now and see how he feels later?