Cancer? I have been bleeding and I had hysterectomy years ago.?

I had partial hysterectomy about 6 years ago. The problem is that a couple of months ago I started haven a discomfort on my right ovarie side. The pain travels in a straight line to my back and to my upper leg on that side only. Something that concerned me more is that I was standing doing nothing and all of a sudden blood rushed out of my and stained my clothes a lot. I am scared. Could it be cancer? whet type? help. I will be going to the doctor this week but I just wanted to know if anyone has had this type of experience and what happened. Thanks.