large bowel movements

I hope this is a good place to post this. I have a rather embarrassing problem which I want to find out about. My problem is that I have really abnormally large bowel movements. Sometimes I even clog up toilets. I have had this since high school, if not before. When I was in 8th grade I started to plug up our toilet so often (maybe once every week or 2) that my dad replaced our toilet with a better one. My mom also made me sit on the toilet every night and try to go in order to prevent it from getting too big. I am 24 years old now and these days I have a bowel movement every 1 to 2 days. I don't have any other medical symtoms and I have never talked to anyone about this because I find it embarrassing. I'm embarrassed to say that I actually have into a plastic bag in order to weigh it. Normally they weight 1.5 to 2.5 pounds but I think sometimes they might weight up to 3 pounds. They are 1.5 to 2 inches around and about 2 feet long. 2.5 feet long would be a maximum. I really want to know if there is any problem with this. I feel abnormal, but in reality, I don't even know what normal is. I would like to know what the normal size of a bowel movement is. Also I would like to know if anyone else has had this kind of problem. I guess it is really just an embarrassment, but It can be VERY embarrassing - believe me! Anything you can tell me would be appreciated.