She's about a year old, both of my cockatiels have bald patches, also when i first got her and she wasn't comfortable, she never leaned like this, now that she is getting used to the surroundings she would lean like this, especially if I introduce something new in the cage, like when I change their tray, I would place a newspaper below the cage and then she'll stare at the paper for hours, I think she maybe just curious, because her crest is always up to the MAX.