But I paid with my debit card for the original item then the item I hadn’t paid for? Thanks

Hi there, I’m having sleepless nights with worry About 2 weeks ago, I went through a self check out and bought 2 things, one of the things was under my arm as I was on the phone at the time. I forgot to pay for it (no sarcasm please) I left the store, showing how innocent I am, I was stood looking in the window of the holiday shop next door browsing at the offers, the security guard approched me and said you hadn’t paid for an item I went back in store, paid for the item, apologised about 8 times. I paid for the item then he said can you come with me, I went to the back office He asked for my name and DOB No address or ID was asked I gave my correct details but obviously there will be more than one John Smiths in London. He said you’re banned for life from all sainsburys and told me to leave. I still apologised; saying I’m sorry Then I left. I haven’t heard anything since? Should there be issue? Would rather just know, but even then it’s hard to see how he’s ever get in contact unless I went back into a store. I work in a financial services job, so was relieved he didn’t ring the police etc, even then I think with no previous criminal record I could probably explain my actions and be let go, as I’ve never been convicted of any offence or even spoken to the police in my life. Can anyone advise? Thanks