Probation extended can they do this what should i do?

Ok so i have been attending domestic violence classes i would finally be released in aug 2011.i went to class and i had to tell a story so i told my teacher about a time when me and my girlfriend got into a altercation and i grabbed her and left her a bruise on her arm he got upset and said he didn't know if he liked this and that he would have to speak to my probation officer about this.so he did and they had my probation extended another 3months which i have to pay another $300. i don't understand why they did this this happened before i was ordered to attend these classes...my probation officer said the only way the y can release me is if my teacher says what he said was a mistake but refuses to do so...what can i do????i don't have time or money to continue to go to class....besides this happened in the past i did learn from the classes i shouldn't be punished for my past...any help???