Very rarely, I have nosebleeds in my sleep and wake up part-way through. One time, I'd had a nosebleed combined with especially restless sleep; I'd been flailing around and wiping at my nose, thus getting blood on my face, the covers, and smeared on the wall by my bed. That was an interesting experience to wake up to.

Not quite the same as the walls actually bleeding, though. That would possibly be more disturbing than an oompa-loompa encounter, because it's less explicable, less natural and simply less human.