Welcome to Over50sForum! The site for people over 50 to chat, make friends, discuss, share, and generally be part of something that's fun and friendly :)
Yes, they will lick at a wound, but depending on the severity of the wound and how often they are poking at it, they can make it more inflamed and worse by not giving it a chance to dry and heal.
What sort of wound is it? Do you know how he did it?
Is there anything in it - like a splinter, or thorn?
Could it be a tick bite?
I would examine it closely and if it doesn't heal, take him back for treatment or even a stitch or two.