Bowel problems

I have been experienceing horrible bowel problems for about a year now and its gotten to the point where im goign crazy.  I will be fine one week then the next horrible.  My bowel movements change consistancy frequiently.  One time it will be fine and ill have to push hard to let it come out then the next it will be runny.  I sometimes have abdominal pain associated with it.  If anyone has any ideas any at all what this could be please give me advice

 

Check out this:

http://en.wikipedia.org/wiki/Image:Bristol_Stool_Chart.png

and then go your GP. He might be able to set you up with a gastrenologist.