What Causes Blood Inside The Ear With History Of Inner Ear Surgery?

I had surgery on my inner ear 2 years ago to remove a cholesteatoma which all went well but this morning i woke up to feel wetness inside my ear only to find out that it was blood. Im not sure if the surgery is connected to this but i thought i would inquire anyway. I hope its nothing serious as i havent had any trauma or pain to my ear. Many thanks for any advice you can give me.