I think staff turnover is probably the biggest issue there. Familiarity and routine is what children do well with, in my opinion, and frequent changes in his care givers at school might be part of the problem. I don't think he is too young. Our son had about six months out of school, from age 9 to 15 months when we moved from California to Colorado. Everywhere we went and he saw other children, he was SO happy and excited.
You might look at a different school. Check to see if there is a Lutheran church in your area that has day care for the little one. And, they tend to have LOW turnover rates. Religion aside (I am not Lutheran) they have excellent programs for small children. Our boy is three now, and has been going to the same school since July 2008. The teaching staff that was there when he started is still there now. One teacher left, but given the state mandated student/teacher ratio, the school did not need to replace her. So, for almost two years our son has seen the same teachers five mornings per week. I think that has been the key to our success, based on what I have heard from friends with children at "chain" schools.
BTW, because the schools run through the Lutheran church are NON-profit, the tuition is relatively cheap. Full time at our school is about 800 per month, which is a bargain.
Good luck.