yesterday as i was leaving a conveinience store i did a pretty bonehead move and i believe i trashed a transmission component when it happened. while i was backing up, before i had completely stopped rolling backwards i threw down to drive and by the sheer force of the shift change, i knew something wasnt right.seemed to have an extra forceful forward lunge (btw 93 grand cherokee 318 and i believe a 46rh trans) followed right away by some forward slippage that seemed to go away as i continued to drive. however 3rd gear is gone now aswell as reverse. as far as reverse goes, i cant feel trans shift as if it were in reverse it just wont move. maybe just a slight amount of reverse power but not even enough to back in a parking place. can anyone enlighten me on what ive done or how to correct this. band adjustment? clutch pack? it did not come up with any codes trans or otherwise. any imput would be greatly appreciated at this point...