A couple of times in the past work has got me pretty stressed - normally driven by me feeling responsible for something that has gone wrong. Work wise I deal with it by trying to get to gym and just tackling the issue head in in manageable chunks. The main manifestation would be a stress cough and being a but withdrawn and switched off in the evening. 18 months ago work was tough!
Two things have changed me a bit both about 18 months ago. One a very senior colleague who is the last person you would expect to be stressed got very tired and stressed and had a panic attack. At the time all the symptoms were of a heart attack and waiting for 30 mins whilst paramedics were battling peak hour traffic trying to deal with it was awful.
Around the same time my 4 year old got an acute burst appendix which was mis diagnosed by a few doctors ( very very rare in young kids and identical pretty much to gastro) fortunately on the 3rd visit in 3 days the most worried doctor we know kicked us off to the kids hospital. Seeing her in intensive care for a few days and sleeping with her on drips and tubes having stomach drained etc was mind numbing. It actually put me in a calm focused zone when I was there with her , but the nights at home when my wife was with her were murder - didn't help that my wife was 32 weeks preggers with an SUA that meant risk of smaller and earlier baby.
In the end everything went well, a week in hospital and then she came home a few weeks later she was 100%, baby came fashionably late and all ok and things calmed down. It changed me a lot though and put things in perspective and as bizarre as it sounds I have been virtually stress free since and if I get stressed I go to the gym and have a think about what happened, how everything turned out ok, try to focus on what really matters in life.
The key is though that sometimes stress or anxiety is situational and you can deal with it like this, sometimes it is medical and this needs to be addressed.
As for work the only advice I can give is speak up ASAP, whether bad news, whether an issue or concern, whether it is something bothering you speak up. Putting things off, going and froing can eat you up and hard conversations are never as hard in reality as in your mind beforehand