If the hospital sent him home after a thorough check up, with the advice to attend his GP, then they're obviously not overly concerned.
I know it's worrying, but that's the reality of it. There's no point fretting yourself or him over it, especially if he is otherwise fit and well.
Chill out over the weekend, do something light but that's a change of scenery if you can.
I really hope it all clears up very shortly
atb,
M