My dog saw me fall and now won’t come near me.

So today, I slipped on the stairs and fell pretty hard. My dog was right behind me and got scared when I yelped. I'm fine, just bruised, but ever since then he's been avoiding me. He keeps peeking at me from the doorway and won't sit next to me like he usually does.

I tried to pet him, but he just sniffed my arm and backed up again. I'm worried that he thinks it is his fault or that I am mad at him. It wasn't his fault at all.

Is this just guilt/confusion? Is there something I can do so he knows everything is okay?