I played the whole game and I will give you my thoughts on it as it seems like you are still testing it. Ignore my low rating please.
This is a nice game (I enjoy Sokoban myself), it has good music, good looking graphics and the left handed controls give it an excellent touch (it's something people tend to forget, but I would maybe mention what the controls are because one doesn't really guess them). There are too many Sokoban games out there so it is not really original but that's OK.
My main and biggest complain about your game is the difficulty. I was done with the game in one day! It is far too easy. Most people will disagree, but games nowadays are too easy and unchallenging. Here is a tip: the more boxes there are and the bigger the level is, the harder it is. I would try to find some harder levels, still including easy ones so that everyone could enjoy. There are so many levels available out there. Another mistake that made the game easier was to include similar levels, for example levels 8 and 9 and levels 22 and 23. The trick for those is the same, if you can beat one you can beat the other, there is no challenge. Work on making this game more difficult.
Asides from the difficulty, there are other little things that could be improved. Such as adding many more levels and showing how many moves you have made in each level instead of just the total. That would really help as it is the only thing that keeps me playing: improving my score. Talking about the score, how do I submit it after I have improved it? You need to work on that too. Give people a way of accessing and submitting the improved score, not just in the last level.
You could also give a creative turn to your game by adding levels with 2 characters that would work on separated parts but still in the same level. You probably lack the skills to make many good changes to your game, I can't help it but to give you my suggestions and opinions. With time, you can get there.
I think the music needs to be louder.
The sound effects for when you mouse over the buttons are annoying as well as the repeated sound of hitting a wall. Once is enough. I still enjoyed it nevertheless.
Good music you picked, if you find more of the same kind you could add it to the game so it's not so repetitive. Loops tend to get annoying.
I like your style and the colours too. I don't have much to say other than I didn't really like how the levels from 10 to 30 look. I find the first 10 levels really good looking but the rest, specially after level 20 with the bricks, are not so great.
I also think that an overhead perspective of the little man would be much better.
And since this is digital art, you could make the game resolution (size of the screen) much bigger.
I think it's a little weird.
The way "Sound" is a button and not an icon in the menu for example. (Not to mention you are missing separated icons for sound and music.)
I think "Play" should take you to where you stopped playing instead of level 1. It could also be merged with the "Select level" button.
A link to your e-mail or whatever you have there doesn't seem like a good idea, at least I don't see that kind of stuff in other games.
I noticed there was no custom right click menu, this would prevent players from cheating. You can look up on how to create one.
Finally I would just like to mention a little bug. You can keep on moving after you fall into the hole (if that's a hole) at the end of the levels. It's all right. I liked playing your game and it's understandable that you may still be learning. I hope you improve this game instead of leaving it behind. :) I hope I didn't fail at reviewing again too...