Can you go to bed earlier during the week? And you are working 5am saturday to 4pm on Sunday with only 2 hrs sleep?
Oh Jon, this is the reason for so many of your problems. You're not getting proper rest, you have very high acetylcholine and norepinephrine levels from this crazy sleep schedule.
Is there any way to get to bed closer to 10:30pm and rise by 7:30am on weekdays? How about weekends?
Those hours you mention sound just like a friend of mine who works in his parents Chinese restaurant in London (UK). He smokes, which makes it worse. He goes to bed as late as 4am some workdays. He's starting to have some health problems - and he's very thin. Another who has had similar lifestyle patterns for nearly 6 years now has type II diabetes, and he's not that much overweight (he too, worked late nights in restaurants nearly round the clock, had few days off, and smokes (still does). He's a fantastic artist, but he's already been hospitalized for circulation problems in his leg. Both of these friends as smart as whips, very cool guys. They are also in need of help; I bite my tongue and say nothing, its not for me to judge.
You came to me, however, for answers.
My response: change this pattern soon, VJ. The anxiety can boil over to much, much bigger issues - and these will be very difficult to reverse.