Actually, this isn't bad for a start. You have a style developing, and you should keep nurturing it. I enjoyed your selection of audio clips that involved a lot of silence from Mark, so you could focus on reactions, but remember to not let them run longer than you can milk the situation. Keep working on the smoothness: add more frames for each movement so you can refine it to be less clunky. Draw your main characters a LOT so you develop a set model that won't change so much from one shot to another. And always keep stretching yourself, and what you think you can do. You're doing well, so don't stop!
Man, this is not, by any means, a good animation. In fact, its stiff, poorly done and overall its just bad. Maybe next time kid. With some more practice you can refine those animator skills, gain some experience, and take your time to do things the right way. Btw I am pretty sure Mark is not black, i dont know where you got that from.