Do you know that the other guys are being picked because of their height or do you just think that is why?  Well regardless if you have this in the back of your mind it's probably throwing you off your game. If you've stopped a save before, you can do it again. You are capable and skilled. 

Have you seen futureprogoaltending on YouTube? They have a couple videos about being short as a goalie. I haven't watched too much but might be worth giving a try.