Yeah they took my name, address and d.o.b what will the letters be that I would likely receive? I just feel embarrassed and panicking and thinking the worst

Today I was shopping in my local Sainsburys, I was doing the scan and go and I put toys at the end of the trolley as was wanting to use a different card. I also had items that I scanned on the scan and go and also had couple of multiple items which only scanned once of the scan and go. the store was heaving and had my son with me who was getting bored. I paid for the scan and go and walked out the shop. I was then followed by a non uniform security card who took me in a back room of Sainsburys where the store manager attended along with the security guard. This was a genuine mistake and I was willing to pay for the toys and other multiple items in which didn’t scan. They advised I can’t and I’m banned from all Sainsburys and gave me a letter. Can anyone advise on what would happen next? I’m really panicking and feel so embarrassed, I’m unsure on how much the items were that I didn’t scan due to them not advising myself