I was a doona stealer well well before I became pregant So much so poor hubbie used to have to tie his end of the doona to the end of the bed !!!! Just to make he'd be left with some cover in the middle of the night.
In relation to waking up would think its a combination of not sleeping as soundly/deeply and then waking perhaps when the baby moves or kicks. Regarding 'stressing' over the noises the animals make you'll just have to train yourself to ignore the sounds. At the end of the day you do know if its a real "help me now" sound or not.
Have you looked into getting one of the pregnancy pillows to help you feel more comfortable in bed. I haven't used them but had seen them discussed on a number of other threads and some mums to be seem to swear by them. Might be worthwhile seeing what their about.
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