I laughed at the message the first time I shrank too much. (Maybe I shouldn't have...)
A pretty unique concept, there have been a few games in this jam about growing larger but none of them used it as the failure state!
The UI text explanations are a bit simple in presentation and I don't think they should interrupt the stage music the way they do.
The controls get wonky when using the mouse to look around since they don't adjust with the new point of view.
Other than that, and especially as your first unique game, great job!