It appears that your were given a sentence of supervisions, which is not a conviction. After you completed your community service, your case was dismissed. If you are unclear about the results of your case,you should consult with an attorney who will be better able to learn the facts and tell you for sure.
In Illinois, the court may enter an order of supervision. After the period has been completed there will be a judgment of dismissal in certain cases.
The statute in part reads:
730 ILCS 5/5‑6‑3.1
... (e) At the conclusion of the period of supervision, if the court determines that the defendant has successfully complied with all of the conditions of supervision, the court shall discharge the defendant and enter a judgment dismissing the charges.
What really spelled it out was when the judge ordered the community service. The papers issued on that date should elaborate the terms. Upon successful completion of the community service required, then the dismissal was entered. It does not mean that there was a plea or any other disposition other than what the order says.
The information provided here should not be construed to be formal legal advice. The provision of this general advice does not create a lawyer-client relationship. Persons with legal questions are encouraged to seek independent counsel for advice regarding their individual legal issues.