I think my brother threatened him...?

[ConvmrsmCrazy]

I'm friends with this guy. I'm 16, and he is 20. Me and my brother go into the shop where he works to get some things, and my brother always jokes around with him. They seem to get on fine, really. My brother is really protective of me. I understand that, but what happened was the fact that when l saw my mate, l walked him up to his house (i have to go past that way to go home), and then we hugged Goodbye, then 2 days later, my brother told me that he saw me with him, and that my brother warned him that I was his little sister, and took his wristband off of him =/.. When l went into the shop the day this happened, my friend didn't say anything. My brother doesn't know that we slept together, but at the end of the day, he doesn't need to know. Do you think he was threatened? My friend was also acting weird, and he hasn't been online. =( He only works part-time, so l have to wait till next week till l see him in the shop. What do you think about this situation?
Extra; I texted him to say that l'll give him his wristband back, but l haven't got any text back. l feel really guilty about it all, now.