Ola Eweje, of Cromwell Road, was holding Kayden’s hand as they entered the store in Millstrood Road when, he says, the electric door shut on him.
But the supermarket says that an investigation has found nothing wrong with the door and that CCTV footage shows no record of any accident.
Unemployed Mr Eweje, 29, who suffers from cluster migraines, says his boy is now scared of walking through doors and has been left with a dent on his head.
He said: “I had hold of him and we walked through and the automatic door slammed shut on his head. Within the space of two minutes this egg had appeared on his head and a massive dent and that was literally just the impact of the door shutting on him.
“He is very cautious of doors now. If it was someone who was younger that could have done a lot more damage. I want compensation.”
Mr Eweje reported the incident, to Tesco bosses and is now demanding an apology and a pay-out. He took his son to the Estuary View medical centre in Boorman Way with his partner Zoe Killick.