Wibbly, yours sounds like the onset of ketosis!
Wibbly, always check first thing as you should be drinking enough to have a neagative or just pale pink reading later on. The ketones will be more concentrated first wee of the day. You really don't want it to ever be dark as that means you are dehydrated.
Ketosis kicks in at different times for different people, I think it depends what you were eating before you started.
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