Bloody Felix!

I walked into our bedroom and found Felix, our 2 year old Boy Kitty full of Blood. Blood was all over our bedspread. I rushed over to him to tend to him. I took him into our bathroom to clean him up and to find where the wounds were coming from. As I was cleaning him, I noticed Felix had no wounds, he was just stained with blood. He had blood on his mouth, that also came clean once I wiped it off. Felix was fine! I went to go look at my other cats to see if they were injured, Nope, no injuries at all. No Blood anywhere else but on our bed and on Felix. Which leads me to believe that Felix must have caught 'something' and Killed it, Injured it and/or Ate it. I looked everywhere, I found nothing. Felix does not go out side at all. He only goes on our 2nd floor balcony. I can only guess that he must have caught a Bird. I really hope that bird escaped or he ate the bird completely......I do not want to someday find the grisly remains.