In general, when a person enters a plea to something, they are agreeing to go with the offer from the prosecutor (provided the court agrees) or agreeing to defer to the judge's decision regarding punishment. The punishment meted out is what it is. Once a case is pled you can't really change the terms of the sentence by applying for a program or anything like that. If the terms of the sentence are overly harsh or if there was some injustice done during the plea (rights were not explained, etc.) then a defendant can petition the court to withdraw their plea and, sometimes, they are allowed to do so. You should speak with a criminal defense attorney in your area as soon as possible. Withdrawing a plea needs to be addressed within a very short time after the original plea was entered.
The final document, "Final Disposition" on file with the Clerk of Superior Court in the county where you were sentenced contains the terms of the sentence. I would suggestyou obtain that document and have it reviewed by a criminal defense attorney who can advise you accordingly.
Sexual Battery is a misdemeanor in GA. You have described a felony sentence. I think you may be mistaken regarding the offense. In any event, following conviction and sentence, there is no mechanism to reduce the sentence. However, you may attack the original conviction with a Petition for Writ of Habeas Corpus.