Perhaps it's a sign of getting old, but over the last 10 years or so my unconscious has taken to keeping all the worry to itself. Thus my upper levels of consciousness are apparently calm and rational and taking everything in their stride, but underneath there's this frantic turmoil of which I am somehow completely unaware. It's only when whatever it was I was worrying about is over and the deep worry has gone, that I realise it was there all along.
It's a bit like the noisy fan on the computer in my office. I don't hear it until, at the end of the day, I switch the machine off and realise how deep the silence has become.
I'm not entirely sure this is an improvement over the earlier years of my life when I'd have that conscious, nagging worry and tense sick feeling at the base of the stomach whenever anything stressful was going to happen. At least then I knew I was worried and also knew why. Now I find I'm reacting to something I'm unaware of, but it does affect my behaviour nevertheless. I then need to do detective work on my own brain to find out what exactly it is that's stressing me!