Well,seeing how your aged 30 and you appear to be in good health(from what you've said),and no signs of any possible kidney problems,which your pains are in the proximity of your right kidney,and the right kidney is slightly tilted,which is more inclined to experience pain.
That being said....no issues there.
You've gotten yourself too focused on colon cancer,which I seriously doubt is the problem in your case,and it's a medical fact that those who do have colon cancer.....also have other symptoms.
So,this rules out that diagnoses.Most colon cancer patients often times complain of rectal bleeding,and you have failed to list this as a symptom.
You should basically assess your situation and ask yourself IF your having bowel movements on a regular basis,which for some people would be 2 bowel movements per day.And,if your not having regular bowel movements and are also experiencing trapped gas? Then this is most likely your diagnoses.You above everyone else should know your body better than anyone,and if your bowels are irregular...then it's basically your diagnoses along with trapped gas.Both of which you claimed offered you relief when released.
Hope this helps.