4/16/2007, I was arrested and charged with grand theft with an adjudication withheld and put on 2yrs.probation?

on 4/16/2007 i was arrested and charged with grand theft although the officer and loss prevention stated that on the video i didn't take any merchandise i was with an ex friend of mine that was stealing i separated from her and went on my way and before leaving i purchased my items that i grabbed and saw that she had an overnight bag that looked full i didn't say anything about it.. i continued to purchase my things and as were walking out officers showed up since it was over $600.00 dollars of merchandise that was in the bag officer s stated that we both had to get booked...i was put on probation for two years with an adjudication withheld and was also terminated a month early am i able to get it expunged or at least sealed and will it show up in a background check????????? and what exactly does adjudication withheld mean?????ive been trying to get some research on it and always comes to dead ends.....my manager has been trying to promote me to an istant manager position and ive refused twice already and explained to her why...ive changed my life completely around im a part time student Single mother with a part time job and trying hard to better my life for my kids and really need some good advice im stuck if anyone has something that can help me out please respond....thank you