Fernando Alonso is to have further medical tests after being released from hospital following a precautionary check on his back.
A medical alarm was triggered in the Spaniard's Ferrari when it crashed down after hitting kerbs at more than 150mph during the Abu Dhabi Grand Prix.
Alonso said on Monday that he was still suffering discomfort in his back.
"The night was so-so," he said on Twitter. "I will do more tests and try to be 100% as soon as possible."
Alonso's manager Luis Garcia Abad refused to say whether the double world champion had concerns about being fit enough to take part in the US Grand Prix in Austin, Texas, from 15-17 November.
"We are not talking about Austin," Abad told BBC Sport. "We need to check everything's OK. It is nothing more than normal control of the situation."
The sensors in Alonso's car measured the impact at 28G when the car landed after taking off over kerbs as he ran off the track avoiding the Toro Rosso of Jean-Eric Vergne.
The alarm is triggered when it exceeds a G-force of 18, and means the driver must go to the medical centre for a check-up.
Alonso was then sent to hospital for what a Ferrari spokesman referred to as a "normal precautionary check requested by (governing body) the FIA."
The 32-year-old conducted media interviews after the race in Abu Dhabi before going to hospital.
He said at the time his back was was "obviously a little bit painful because it was a big hit."
He added: "Hopefully I am OK for Austin."
The incident happened as Alonso left the pits following his final stop on lap 44 of the race.
The pit exit feeds into the 155mph Turn Three. Alonso came out alongside Vergne and had to take avoiding action as the Frenchman moved over using the full width of the track. Vergne admitted he had not seen the Ferrari.
Despite being launched over the kerbs, Alonso passed Vergne while running off the track but was cleared of wrongdoing by race officials, who accepted that he had no choice but to run wide as Vergne had left him no room.