Don't worry Kim,
The first night is normally with just a clip-on probe on a finger, it measures your heart beat and soluble oxygen in your bloodstream.
The sleeping wards can be mixed and a little noisey.
The following morning you will talk about the results of your sleep test, if like me you stop breathing during the night, you may be asked to stay another night with a mask on a cpap, an amazingly good machine which keeps the airways open.
Take some bread and visit the pond, just like my swim last week [

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