I think they have a lot of buttons.
Perhaps it would be better if you kept control of the vines on the mouse, control of the caterpillar on the keyboard.
This would make it easier to understand the controls.
Configuration example: Select the vines at the click of the mouse and with the mouse scroll, grow and shrink the vines.
Do not dedicate a button to turn the caterpillar, but already include the action in the "A" and "D" keys themselves.
I recommend Donald Norman's book, The Design of Everyday Things.
Congratulations for the game.