Good job on this one! Nothing like a nice, tight platformer. I will say getting to that first sunbeam is way more punishing than the other ones lol. I wish there was some kind of indicator that you were running low on health. Maybe a sound effect, or have the character visibly wilt or something.
One thing I noticed: Sometimes I'd see dark lines appear between tiles as the camera moved. Moving the camera in Godot can give you floating point rounding errors with the individual tiles in Tilemaps, which causes the spacing between tiles to get inconsistent and weird. You can fix this in the project settings by going to "Rendering > Quality > Enable Pixel Snap".