please correct me, this what i assume:

- head lifted up, but the head stays horizontal = periscoping, normal behavior, rather rare rather cute.
- head tilted upwards, nose going up = more unusual, healthy BPs only do it to smell the ceiling or when climbing.

does that resemble the truth? the way you describe it, it may be a BP periscoping/sniffing out of boredom/curiosity.

im no expert, but i see you jumping from one symptom to a diagnosis, while many things could cause the symptom. relax