I liked this interpretation of the limitation. It's a bit more metaphorical, and gives the game a more cohesive overall theme. I can also appreciate how the UI design communicates the character's anxiety. (A very relatable feeling, tbh.) The art and music are also good!
However, I found the actual gameplay to be frustrating. Managing health, mana, and character position, all while also looking for the right spell to cast, was difficult in a way that wasn't fun for me. The position of the health makes it feel like it's the slime's health, so I was confused the first time I died.