Testicles Question

[Abigail]

So DS is a boy. When he was 12 months old his testicles were checked to make sure they had descended as a routine check. They had.

When he is cold his scrotum shrivels up and his testicles disappear... as far as I know thats pretty normal?

My concern is that when that happens lately his scrotum shrivels up but his testes appear to disappear up on one side of his body. So that he has a large swollen area near where his leg and penal tissues start (his groin?) on one side only. So he has one really swollen side and one normal shaped side... He tells me it doesnt hurt but is it normal? To be swell like that so noticeably as well?

Should I be getting this checked out?