I'm not sure the buttons like that were allowed, but the gameplay does abide to the limitations, so I guess it's fine?
Anyway, the core of the game is good. You actually implemented a little bit of an RPG mechanic where you get stronger with each enemy defeated, and move through this little gauntlet.
The 2.5D graphics are actually my favourite part of the game - the way the bird walks and the fusion of sprite on the 3d level is a good touch to differentiate it from just going 2D.
There are some quirks here and there with the gameplay - for example, using the attack would make you dash forward, but trying to walk and attack would usually make you stop in place, strangely enough. And sometimes attacking the enemies hurt me instead of them, which was a little frustrating.
Even with these quirks, I'd say this is a good entry, and I had my fun once I knew how to play. Good one!