Re: Grumpy
No coffee and plenty of exercise does it for me. Wipe out. If I can't sleep I don't force it and try to sleep I work around the clock then normally. Hard exercise nearly always works though. If you can't exercise for some reason or other then I suppose you have a problem but a long walk and plenty of fresh air might do the trick too. Also reading when in bed helps me nod off. Just a few pages is enough normally.
I have a mate that would stay up all night and sleep during the day. Became a habit with him and he still has it. I prefer to get up early and go to bed at a reasonable time.
You can definitely reprogram your sleeping habits if you really want to but being unable to sleep can sometimes be a blessing. It certainly is for me if I have a huge amount of work to do.
Go with the flow for now but rise early - no stimulants (coffee - alcohol) - and get plenty of fresh air and exercise to get back to a regular sleeping pattern - hopefully
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