2010 audi a4 b8 2.0 tdi sline dsg automatic

Hi there, I'm posting this as I'm struggling to find any useful information that could help me. 

I have a audi a4 2010 b8 2.0 tdi sline automatic while driving recently on a motor way went for a over take while manually changing shifting down in gears on the display it showed a gearbox malfunction drive limited noticed the glow plug symbol came on along with engine management light car was showing alot of white smoke from exhaust while the car started to absolutely shake and rumble uncontrollably managed to get car home done a diagnostic showing a misfire on cylinder 3 and oxygen sensors 1 & 2 recently changed injectors and coded them but car is still misfiring on cylinder 3 I'm not sure what I'm todo next has anyone else had any of these issues above and could share any light on this issue I'm facing? Thanks...