What happened? Huge egg and blood

OK, I'm really wondering what is going on. I had been getting 2-3 eggs a day until last weekend. That's when I discovered the "other" nest. So for the last 7 days I have gotten 5 eggs/day from 5 chickens!!! What happened to shorter days and less laying?
But today something really strange happened. When we checked for eggs in the morning, we found 3 in the nest box. One was bigger than any we've ever seen. I get a fair number (~1/10) of jumbo double yolks. But this is HUGE. I haven't cracked it open. Do triples exists? The other 2 eggs were in the coop out of the boxes. Most of the straw was out of the nest boxes. The wood shaving were scattered in the coop. There was what looked like blood all around the boxes. There was then blood all around their waterer in the run.
I would think that the chickens were fighting, but I don't see any noticeable wounds. Where should I be closely examining? Does the huge egg have anything to do with this??? It's really weird. Yes I'm new to chickens... Just had them since spring.

 

I will try to post a picture of the egg. I'll try to check their vents today, but it may be dark by the time I get out there. There wasn't any blood on the egg. I didn't notice any blood anywhere other than all the walls of both nest boxes and all around the water which was really strange. Hopefully some of your hunches are correct in that it's the vent and not fighting.