It is just a littel soap in his "pee pee" as you call it. This has happpened to me once before and it is not fun. I amagian he is in a lot of pain. Hers what you do. Take his penis/pee pee and open his hole flush it with water. If the pain dosent stop. GO SEE A DOCTER!!!!!!!!!!!!
A seven year old may be able to describe the pain with more details. If you're considering the pain coming from soap in the meatus (penis hole) then you could ask him if it hurts there. An infection usually causes burning when urinating and frequent urination and is unlikely in young boys but must be seen by a doctor if that's what he has. A kidney stone causes blood in the urine and pain in the back on the side of the stone.
Dr. Enoch Choi, MD
Palo Alto, CA
the foreskin and head of the penis are very sensitive to soap.from now on tell him to just wash with water and a washcloth and when he gets out of the bath/shower to pat dry his penis/foreskin and then immediately cover his penis with his foreskin.this is the most comfortable way to go if he doesn't do this he will continue to have pain.