I Suck at Black Ops Ps3!!!?

I used to play the wii version before i got the ps3 and black ops, and now im really terrible! im so pro! id average around 30-7 a game on wii. on ps3 i average 6-19 it's awful i get soo mad! everytime i turn a corner someone kills me! any tips on getting better? my Gamertag: Traynee-N1NJ4- also im a Rusher im not a camping no lifer!