I am sorry to hear that you are having painful bowel movements and are worried that you may have colon cancer. You also mention that you have lost a lot of weight. I am assuming that your weight loss
has been non-intentional. There are lots of questions that I would like to ask you to help figure out what might be going on, and why you are having the symptoms that you are. This is something that ideally should be done in the setting of a doctors
office where they will be privy to your entire medical history, records, and will be able to examine you. I commend you on already making plans to go get checked out by a physician. With the little information that I have thus far, it is impossible for me to tell you with any certainty exactly what is going on in your situation. I am sure that you have already heard from somewhere, or read on the internet that significant unplanned weight loss can be one of the signs of a caner. However weight loss can be a part of innumerable other medical conditions that I can't tell you (nor can anyone else) tell you for sure that you do, or do not, have cancer. It is the job of the physician to help determine what might be going on, and part of that will be determining, and hopefully ruling out, cancer as a cause. I hope that this has been somewhat helpful, and I wish you all the best.