Canon 6D or 7D for indoor sports (volleyball)

Ok, so please forgive me for asking a question that I'm sure has been asked way too many times.  I just stressing out because I have read too much!

All I am looking for is a dslr camera for my daughters indoor volleyball games.  I am just starting out and have a lot to learn.  I just want a camera that will give me a nice clean shot, no blurryness.  I just recently purchased the Canon D6, based on what I have read I think I should have ordered the D7 even though it's an older model.

Any input? Please......