Go for pardon or fight?

10 years after getting a crimminal record I'm told to apply for a pardon, At the time my lawyer told me I would spend more time in prison waiting if I plead not guilty, whereas I would get out sooner if I plead guilty. I know not what the charge was and the judge told me I pled guilty to a crimminal code number, without asking me how I plead and what the actual charge is. Now I'm told by people I should go for a pardon. Should I fight against an unjust system or go for a pardon? .Who can help?