for a person with no prior record what so ever? am I looking at a fine or what?
That depends if it was on purpose. If it was an accident, there shouldn't be a criminal penalty, but you can be sued for the cost of the repair.
Criminal Defense Attorney
Whether you are charged criminally depends on the alleged facts of the case. If you broke the window, for example, because you were throwing rocks at it, then you may face a criminal charge of malicious destruction of property. If you broke it because you tripped and fell into it, then there has not been a crime committed. If we assume that the facts implicate a crime, the fact that you have no prior record would support a dismissal upon restitution (i.e. paying for the window) or a continuation without a finding.