Hi, it is my second jam but I documented postmortem and lessons learned from my first one done this January (Blackthornprod 2021) here:
https://createev.itch.io/greedy-honeypot-in-rock/devlog/219130/greedy-honeypot-i...
I also done the same for this jam - here is a postmortem for my 2nd game jam: https://itch.io/jam/brackeys-5/topic/1231056/yin-and-yang-in-search-of-harmony-l...
Hope it will help you in your gamedev journey!
Andrey "Createev"