As the artist of my group, and an ardent bird enthusiast, the art in this game was really cute and done well. Have some more confidence! While there's technically not a failure state, the main core of the game is fun.
I would advise against putting the whole hitbox to include the flower, and to make the hitbox itself a little smaller than the player so that they can have an edge in weaving through smaller birds, especially towards the end.
Additionally, having a dedicated "drop down" button would make the game more playable as often I flew too high and had no way of dodging other than gravity.
I definitely think, given more time, this game could be completely polished. Keep up the good work, and good luck!