D.K.
Try giving him motrin or tylenol to see if that helps the pain. If it does more then likely yes it can be growing pains. If the pain gets worse or is generalized, take him in for a check up on it.
Both of my kids have gone through pains, it isn't in one specific area though and tends to be more around the muscled areas of their legs like calves and thighs and such.
If the pain persists more then a few days I would take him in. Also he could have had a charlie horse during the night at some point, or even pulled a muscle.