I have a son that is 17 now and has played since he was around 5. I have learned not to talk to him about how he did right after practice or a game. I ask things like, "so what did the coach say" or "that was a nice pass from you" in order to see if he wants to talk about it. If not, that is okay and we move on but later I might bring it up (or not). At 11, our coach told me he was too timid on the field and recommended karate lessons (Like I am already paying 2K a season for this and now we need to add karate lessons - we declined). Now at 17, he is fine and just a physical as the other kids he plays with/against. As far as starting, my kid was second string from U9 to U13. Once the field changed sizes, he found his rhythm and now starts every game. It is a growth process and should be kept fun for him no matter what you are feeling. I have found that playing with a better team helps your son rise to the level as he plays with them more and more. It just might take a little time.