Something similar happened to me today on my K-70.
Trying to be "clever" and swap a lens whilst stood on a cliff without actually looking at the camera, I managed to push the switch to "movie" rather than "off" before removing the lens
All sorts of noises from the body made me realise my mistake and I switched the camera off before refitting the lens.
With the power turned back on I was presented with an unfamiliar combination of shutter and aperture settings, switch off and back on again and things were "back to normal".
So, it would seem that un-recommended procedures can cause unexpected results ... fortunately no harm appears to have been done