I am addressing two issues at once because the screenshots depicture both at once. I hope that is no problem. Anyway, as visible in the attached pictures it is possible to push the villagers around in their bed to a great extent. One can push their heads into the wall, for instance. Regarding the other issue, it seems like more than one villager tries to sleep in the same bed. While one is asleep, the other one stares at them the whole night. They even ignore other free beds as if they wanted to claim the occupied one.