Still need some work.
Judging from the fact there is no sound, im guessing this is one of your first, my advice to you is this - Redirect your efforts to one thing at a time, try and learn about sound and get really good at making the sound match the right part of the animation, and getting good quality music.
After that i think you should consider what you are going to be, sprite artist, flash artist, or both, and practice the animation in which style you favour most.
Take one thing at a time and you'll be fine.
About the animation - The sprites were a bit 'dated', by that i mean that the sprites were pretty old and i think you should've gotten sprites from a game more recent like 'Super Mario World' or 'New Super Mario Bros.'
the humor got dry after a bit but you had some funny ideas, that sewage pipe gag with the turtles was pretty original, so keep that up.
Good luck getting better. =)