Thanks! The ESC button was added at the last time. Sorry about that. Moving the character with the mouse would definitely be a fine addition, as well as checkpoints.
I was hesitant to remove this but at the end I left the character to only walk. However, you can pick some Painkillers from bathroom and, once you consume them, your back-pain is gone and you can run. I agree though that it's way too hidden and should be highlighted or even be part of a tutorial.
Regardless, thanks for playing!