Your credit report will be fine. Barclays will be the only lender who knows you were late. It's possible that there may be some limitations on this one card for a while, such as being ineligible for a CLI in the immediate future.
My thing would be that you call them, and ask for a LATE FEE Forgiveness, say we totally forgot about the bill, and mistakes happen. No credit report hits or anything will happen unless you totally miss it for more than thirty days.