Am I At Risk Of Colon Cancer As My CBC Report Shows A Mild Case Of Anemia?

Question: I am writing because I am worried about colon cancer. I recently had a blood test by my cardio doctor and my CBC shows mild anemia at a hemoglobin level of 12.7, which is now lower than my last test in July of last year at a level of 13.6. In 2013 it was at 13.8. I have additionally had some gastrointestinal pains for the last couple years, but my GI doctor has chalked it up to IBS and fibromyalgia.

As I have read anemia is one of the symptoms of colon cancer, are these levels something to worry about? Or does it have to be lower to be a symptom of cancer? Or would start decreasing in a more dramatic fashion rather than slowly and gradually?

I have also recently been having very painful intestinal and rectal spasms, which also have been causing changes in my bowel movements. When these bouts occur, I have 4-5 BM's/day with small stools. They also are quite dark stools, but not the tarry, black kind that are said to be symptomatic of colon cancer. Usually, these flare ups subside in 3-4 days and I go back to being regular. But these flare ups have been happening more frequently, along with gas and bloat.

Thank you and please advise on any action I should take.