Does my Mass Effect 3 DLC from Xbox 360 carry on to the pc version of ME3?

I have al lthe DLC for m * effect 3 on the Xbox 360 and I switched to pc and I bought all games and I have played them all fully except ME3. I wan the DLC and I refuse to pay 12 when the Xbox version is cheaper then PC version. I also wnat my pre-order bonuses and N7 guns and armor ect becuase I bough the collectors edition.. Also I bought the game of amazon for 5 pound. Why should I pay 9 pound in the first place?