I left my job at the supermarket on thursday.
Today I got a letter from the supermarket's overall HR department saying that they were writing to confirm that my leaving date will be on the 11th June and will be paid accordingly. That's next week!
I'm going to the supermarket on monday in the hopes that I can explain things to the office staff. I hope they can sort things out before I'm overpaid and before the incorrect P45 form is sent.

Can't stop worrying about it.