Great advise from Aaron...
My take, your dollar amount is low and not enough to force a felony conviction on the amount. Your actions of resisting detainment WHILE committing theft resulted in a FELONY robbery charge. Its quite the same as Punching and old lady and taking her purse (in the courts eyes).
I know that your screwed in my state with a F5 (Felony) fifth degree
when you sock an LP here. That will land you in jail / prison. Your first time offender status is the only thing that will get your sentencing lessened a bit.
Just don't expect it to come out like a normal shoplift slap on the wrist.
You went a step above the typical shoplifter reaction. Sorry.

