Kito and Abbey had a few small scuffles when they first started living together--Kito took a small teeny tiny piece of her ear off, and Abbey retaliated by giving him a nice puncture in the shoulder.
A few months ago, they had the worst fight ever. It was entirely my fault though---they were fighting over a big ham bone--I shouldn't have given it to them. This resulted in 10 stitches for Abbey, and a $300 vet bill for me.
After that, I kept them separated for a while when I wasn't home, it just makes me feel better.

I hope everything is ok, they probably just had a disagreement of some sort--I would just watch them for a while, and I'm sure they will be back to normal soon.