You really should try and complete everything within your given time frame. Failure to do so will likely result in a Petition to Revoke your Sentence and if granted, you will be resentenced. Also, if you do get an extension, this means that you are under the Court's thumb for even longer which is not a positive thing.
While there are no guarantees, if you are in compliance with all other conditions of your sentence and, ideally, can make a partial/good faith payment toward the amount you owe, you should be able to request additional time when you return to court.
Possibly. Did you complete the other things you were required to do?