My 11 year old son was playing in a field and ran full speed into a barbed wire. There was no bleeding or puncture but a very large blood bruise formed. It s now starting to change colors but has not diminished in size (this is day 6). He says it doesn t really hurt him. My question is: Is it ok to fly on an airplane with his bruise? It s only a 2 hr. flight but I can t help but be concerned. Thanks!