My Son Is 6 Years Of Age, 7 In Dec

My son is 6 years of age, 7 in dec 2016. I have recently notice visible green veins very prominent on the back of his right calve. Hugely worried. I will book an appointment at my local doctors once we return from holiday next week. A couple of weeks ago my son was complaining of his legs hurting whilst walking but I thought he was just trying to get out of walking. regards.