Swollen ear after stretching?

For some people, yes, it is common to happen. My ears started to do that around that size too. To reduce the swelling, you could do sea salt soaks 1 or 2 times a day, massage your ear (it increases blood flow), or simply put ice on it. Just remember, that if you're ears are like that now, it's more than likely going to hurt more each time you stretch.