Seems like the bases are covered, so I'll keep it simple...

A) so sorry for your loss.
B) one small every 7 days is fine.
C) good on you for stepping up and taking on the challenge of a new animal. Keep reading, keep asking questions, keep learning. The snake already seems to be in good hands with you. I'm sure the departed is looking down happily knowing the snake is in good hands.

Good luck! We're here to help, so feel free to ask any questions you may have.