Breathing rates may change for a variety of reasons and in some sleeping positions the airway may be slightly occluded which may result in altered breathing but without examining Kiki I cannot say for certain whether it is something to be concerned about or not. As for drinking, some cats may drink less that are on a wet food diet but you should ensure that she is keeping hydrated; you should visit your Veterinarian for a general check about the breathing and they can also check the hydration too. Regards Dr Callum Turner DVM
Rapid breathing (tachypnea) is a respiratory disorder characterised by abnormal breathing that is rapid and shallow. It is caused by a reduced level of oxygen, mechanical disorders (where the lungs aren’t able to expand as they should, usually due to a build-up of fluid in or around the lungs), and physiological disorders in which the cat’s respiratory centre in the brain is over stimulated.