Have you been diagnosed with an anxiety disorder?
In general, I think I worry to much, and that results in somewhat of anxiety issues. If I'm out the house, say.. visiting my girlfriend, I'm fine, but at some point during the day I begin to wonder if I have any "bad news" in my mail... ranging from bills, to notes from reposession, to appointments from job centres. Yes, that to me is bad news, because that kinda means that I have to stop doing what I'm doing and I feel I have to prepare for such an appointment, even if that's 2 weeks in the future. And of course the stress doesn't end there... being prepared and hope the talk is a bit like you expect, plan ahead and all, adds up to stress.
Mostly I'm cool on sunday, cause I get no mail, nor email, nor phonecalls from anyone (except for friends or such).
So what I kinda do is at least limit the stream of "messages"... I don't give out my phone number that much, nor my mailadress. Also, while I might suffer a bit from anxiety in such situations, I'm kinda "quick" with a lot of stuff in the sense that I jump on it, and get it over with instead of eating me for days or weeks. That relieves stress in the sense that at least I did my part on those, mostly legal, matters so I can try to get on with my life without being stressed and anxious until the next few days or so.
I think that it might be comforting to try and set up your life a bit. What do you want? What do you expect? And work towards that. Again, speaking for myself... currently in the situation of filing disability and all, so that's pretty much the thing I want to focus on if needed. Make those appointments, seek help to get it sorted out... as well as currently I wrote some companies I had run ins with currently and that stress me out, to send my mail to my moms, so she's my representative for now... I found that his works (but that's hard if you don't live with your parents or don't keep in touch with them a lot).
Also, what helps me relieve anxiety? Doing things I like... that usually gets me through about at least 15 hours a day... that one hour of stress a day, I can deal with for now... not saying I can deal with that in the long run, but for now... it's manageable.