I guess it happened to me once, or maybe more than once, but once my T said something along the lines of: it's not that uncommon for people to regress a bit in stressful situations. I couldn't sleep until I bought myself a soft toy. Toy shops were my absolutely favorite place, went there almost every day. I cried all the time. Played stupid childish computer games and colored a lot. Read story books too. And watched cartoons. All the stuff at work seemed too hard and way too complicated, sometimes I couldn't understand things although I knew I know them well and I did the tasks before. Sometimes I was scared to call ppl I don't know. Coping skills? I kind of forgot most of those. This nonsense went on for a few weeks. That was a scary experience to be honest.