Worrying about it is compounding the worry. I know that's no help. Drink loads of water, (not tea of coffee, water!) cut out as much salt/sodium as you can, bed at reasonable times, and light exercise. You've knocked the booze off, if you smoke, Don't! We've some Union types on here that can listen and understand better about working conditions and unreasonable demands than I can, think it was one of the ladies.
Agonising over an upcoming event increases the stress surrounding it, approach it calmly, "not been for a bit, be a nice change of scene" - "be nice for a day out with the old man" - "they might even turn up just for us, what a plus that'll be". Have the Docs put you on anything for hypertension or blood thinners?
We all want to be 21 forever, but time and tide wait for no one, we all make adjustments as we get on some. Managing the adjustment and giving ourselves an easy ride is paramount.