Parents are just people and very imperfect at that. I have failed my kids in many ways, I know i have complained about things they aren't doing but then forget to commend them when they do well.
But yeah it is a human thing. If we have a friendly cashier, rarely does someone write in and say HEY #13 was awesome today, but if #13 was being a cow then BOY will she hear about it.
I feel unappreciated very often. My kids don't appreciate me (or thats how i see it) they rarely thank me for dinner and would rather complain about what's on the plate, my husband never tells me i am doing a good job with the house or that hes thankful i make his lunch each day for him, but if something ISNT in place then i will hear about it for sure.

Anyhow, sorry for derailing with my own issues and Im sorry that your day has collapsed in on itself like that. When our inner structure is weakened, its sooo easy for anything piled onto us to cause a full collapse. ((hugs))