Diesels Swollen nose incident

Diesel came crying up the stairs the other day holding his head. He was jumping on his bed and went to flop on his belly and hit right between his eyes on the toe board of his bed. I sat and watched it grow and grow..it was so swollen and bruised and sensitive. Now that it has healed there is still a lump under his skin-so im wondering if we should have taken him into someone to help> maybe he has a lot of tissue built up there now.. the poor kid always learns things the hard way.