I wish I knew how to do pictures, I have to get with the program! I have a Barred Rock that is about 8 weeks old and huge. I think it is a rooster because the tail feathers are starting to get long but yet the comb is basically the same as the other three birds I got at the same time which are RIR and definately hens. It's tail feathers are longer than your picture and at 8 weeks does not have the comb and wattles that yours has yet.
I wonder if you did not clip the wings far enough. The learning center has a picture to show where/how far to clip them. I might be afraid to clip them that far, but it says to. That might make a difference on the amount of flight effected.