Hamilton must wait for all-clear
His team McLaren, however, has given him the all-clear after a precautionary CT-scan check at the nearby Bundeswehrzentralkrankenhaus military hospital in Koblenz.
Championship leader Hamilton, 22, returned to the Nurburgring from hospital on Saturday afternoon, and in a McLaren statement said he was "absolutely fine" and wants to race despite the 250kph qualifying crash.
Ron Dennis told reporters that there is "no medical reason" that will keep him out of the car.
But FIA medical delegate Gary Hartstein will have the final say, when he examines the British rookie at 9.30 on Sunday morning.
"I'm feeling fine," Hamilton told reporters in the paddock.
"I'm very fortunate, very lucky I haven't got any bruises -– although I'm sure tomorrow I'll wake up with some."