There were a lot of mechanics introduced during the tutorial and was very overwhelming. As a result, I didn't use shield till my second play through (which I did to figure out what shield was). The game wasn't that difficult, as shown by the fact I beat it first try without shield, which I found pretty disappointing. I think the first level could be cheesed by the fact the player can jump onto the grey bricks, though I didn't test it. Overall, it was a great concept and reminded me a lot of games I played as a child on Webkinz.
If you do add more levels, may I recommend introducing mechanics at a slower pace, so that the player can effectively use all of them?