You haven't let anyone down at all. This is just a minor set back caused by a shitty day yesterday and your H's stupid behaviour.
Regarding this - "Am thinking this is why H gets frustrated with me when I panic and can't do things I should be able to do that others find easy."
No, no, no! Your H is NOT right, don't speak to yourself in his voice for him when he's not there to do it! There is no 'should do' anything, you are coping the best you, or anyone could with a very difficult situation brought about by him. How dare he 'get frustrated' with you when he has caused your panick in the first place fgs. Others may find certain things easy but they don't live with your H. I bet you a lot of others find these things just as hard as you if not harder. They may look like they're coping but everyone deals with stress in a different way.
One eg is me, I felt stressed because my ds had feeding problems, this manifested itself in my anxiety levels rising. Because of this my fear of wasps got totally out of conrtol until I would hardly leave the house unless my dh was with me. I am a lot better now, was always afraid of them anyway but no to that extent.
Anyway, my point is, that was just caused by a small, common problem in my life but you have much bigger stresses to deal with so it's not surprising it affects you in this way from time to time. You'll get there, one step at a time. None of us are judging you, you are doing brilliantly.