No, Marvel time is always 15 years in total and they squish everything together for that. He was still very young before he was on the Avengers and is now no more than 29, because 30 is scary to Marvel. So that time does not move and he becomes older when he became an Avenger. That time just gets squished together very uncomfortably until it makes no sense. Because that's the sliding timescale. And it still includes everything in it, but keeps everyone young. When you start to get into the ages of characters from different generations, it becomes even more messy. So if he's 29, he'd have been 14 when he ran away from home.