It's a start, at least.
My suggestions (though they might be already in your plans):
-make jumping more natural (a simple tap on the spacebar should bring you up enough to get over 1 or 2 blocks; in this version, tapping only gets you ~0.7 blocks up);
-give that character some hair - that'll make him way more attractive =] Believe me, main characters are one of the MAIN worries when you're making a game because they're worth big points;
-replace those numbers with bars and add some decoration to make a nice GUI (I bet you already thought of this).