Lump about 2" inside of rectum

This is embarrassing to talk about. I do have an appointment with my Internal Specialist May 27th and I know that she will want to do a Colonoscopy. I have to have one every year because each time she does this she has to cut out a couple and sometimes several Precancerous polyps. I skipped last year seeing her because I felt fine. Now for the last six months at least I have been terribly constipated all of the time. It got so bad one time that I had to put on a thin Dr.s glove and pull out hard small balls. When I did this I noticed a large lump about the size of a golf ball about two inches inside of my Intestines. When I do go to the bathroom regular which is quite infrequent my stool comes out in long things lines about the size of your finger. I know that this is due to the lump that is inside my Intestine. Could my intestines have herniated inside and leaves a small space for me to evacuate the stool? Do you think that I will have to have surgery to have this lump sewn back into place or could it be cancer? Could cancer be that large of a Polyp (not knowing what else to call it) besides a large lump. I can push it and it is soft but is closing off the opening to my rectum. Does anyone have any insight to my embarrassing problem or has anyone ever had this symptom before. If you can help me understand what this is I would appreciate your help.

Thank you very much,
Sophia2008