Is this a hickey?

I found this on husbands arm last night. When I ask him if it is a hickey he said “Yes it is” and that I did it to him. I know when I put and hickey and my hickey doesn’t look like that. And when ai proved to him that it was not mine. He said he didn’t know where it came from. That we just woke up one day and found it in his arms. And I like, really? You have a bruise in your arm and you didn’t even know how it happened?

I asked a few friends and they said it is a hickey. I know some of you will say that that is mine and maybe I just forgot I did it. I promise you girls that is not mine.

Do you think it is a hickey or he just bruised himself? If it is a hickey how do I find out who this girl is?