In any gamemode, when you go to sleep, if the FOV is over 100 [101 to Quake pro], you will se your head's inside instead of the regular view.
It appears as resolved in following tickets:
https://bugs.mojang.com/browse/MC-39647
https://bugs.mojang.com/browse/MC-19
https://bugs.mojang.com/browse/MC-10651
Fixed in 14w08a (1.8 Snapshot). MC-19