Yeah I can tell

If you weren't impressed with the training school first time round I wouldn't go back again, find a different one.

If it were me I wouldn't make her sit for a treat everytime, going outside to the toilet is good enough reason to get a treat and it builds a healthy relationship to just give treats now and again just because you love them! Try not to make her feel like she always has to earn everything all the time.

Sounds like you are already making some positive steps though!

Amy's very right that it comes from the owner, don't let your dog know you are worrying that she might bite or she will interpret it that there is something wrong and is more likely to bite!