That would be a proctologist. However, a general physician with a working knowledge of mens' health should be able to point you in the right direction regarding the colon.
A gastroenterologist.
smoking can causde a hole in your colon how can smoking cause a hole in your colon
Simply tell your doctor of your worry about colon cancer. You will need to describe your symptoms.
A good colon cleansing formula can be given to you by your doctor. If this is something you do not feel comfortable talking to your doctor about try websites such as the vitamin shop or the colon cleanse guide.
Not nesessarily, a spastic colon is a concern for your doctor , you will need medication
Proctologist
Your doctor will tell you this when you get your prescription - you should not try to treat an infected colon without seeing a doctor.
Coffee colonics will work just as well as a doctor's colonic for the first 2-3 times that you do it. Simply have some lukewarm coffee, and a colon cleanse kit that has the tube, and inject the coffee colonic. It is cheap.
There are colon cleansings foods available. You should actually contact your doctor or pharmisist for a list of foods available to help cleanse your colon
A doctor who specializes in the colon, rectum, and anus is called a proctologist.
May I ask why you know what your colon smells like? O.o You could get a colon cleanser from your doctor. I'm not sure if they sell it over the counter.