Please be careful if you try activated charcoal! I was getting stomach pain 20 minutes after every meal. I finally figured out that my stomach pain started after I took activated charcoal (heaping tablespoon for 2 days in a row - not a lot!). I located the pain in my stomach, found a little lump in the colon, and then used my fist to move the lump to the left. A day later my husband took over, found the lump,(which had moved slightly) and did acupressure for about 2 minutes on the spot-- ohhh yes, it hurt. But within minutes I had to run to the bathroom and the rest is history. No more stomach pain. So please be careful with the charcoal, especially if you have a sensitive stomach! I think that people's stomach aches can be often be an impacted colon. The same thing has happened to me before after eating bread and another time, after drinking psyllium without enough water!
If you press on your stomach and have a painful spot that moves slowly from one day to the next, you may have clogged your colon/intestines. Tons of water helps, but acupressure massage is best to move the obstruction to your bowels and out. One last note is that I was having normal bowel movements even while my colon was impacted, so don't rely on that (constipation or elimination) to judge, but more on the location of pain and whether or not a little lump exists.