Welcome to the forum.

Congrats on starting! That's an impressive distance for a new commuter.

You will work out the issues as you go along. Everyone has slightly different wants/needs. I get by with a rear rack and trunk bag that has zip out fold down panniers as I don't use them every day.

There is no shame in taking a day off to rest. You'll feel like superman when your rested. Be safe and have fun!