Head injury healing

Ok so i just want some experiences from yall. In june my 5yo got head butted on accident right in his forehead/eyesocket. He had a massive goose egg.and busted cheek from the hit. We watching.him.closely and.spoke with the dr and he had no signs of concussion or broken bones. Sooooo now here we are august 1st he still has like a lumpy spot on his forehead where the impact was the worst. We asked the dr last week but she was very nonshalant and barely even inspected it. Didnt listen to how long it had been that way. Ao my question is.if your child got hit hard in.the forehead how long did it take for the knot to fully go away? Should i go get a second opinion?