Sure that would have worked, if he wasnt so darn fast. Since it does take time to do an attack that size, and time is what you dont have, he is out of the way. As you probably guessed, hes behind you. What takes place every time their behind you? Yeah you know the routine, you die from a blast to the back. However, dont get discourage. You see, this is no ordinary blast, Majin Buu used his Self Destruct manuever, you should feel honored!