Now everyone would feel that with her recent string of hits, Katrina Kaif would feel that she's the luckiest girl in the world.But it's really not like that. Apparently the dame is worried and mighty jittery about the fate of her next film- Subhash Ghai's 'Yuvvraaj'.The actress has reportedly says, "I really want this film to do well. This is my first romantic drama opposite Salman without the support of comedy like 'Partner' and 'Maine Pyar Kyun Kiya'. 'Yuvvraaj' is special to me and I