Weird unknown object found in stool, please help. (contains images)

I have had less than normals poo's for about 2 weeks now, they have been on the soft side and smell extra foul but today I found this dark brown thing in my poo. I would say that it was about 3 centimeters in length and it was very distinguishable as it is dark brown and the rest of my poo is a very light brown. It flaked of easy when poking it and it was sort of firm while the rest of my poo was soft. The underside of it was sort of flat and had a small groove running from top to bottom. When broken apart it was stringy. There were other dark spots in my poo which i assume was the same as the big brown thing but i couldnt get them out as they were far deep in the toilet. Yesterday I had a diarrhea poo. It had no structure and I couldnt even really see it as it made the water brown. It had some foam or bubbles on top though which was weird and when I poked it a bit it kind of all moved together it was connected with this slimy stuff I thought maybe it could be mucus although I didnt inspect it much. About 4 days ago I came into contact with dirty fresh water although I didnt drink or get any in my mouth I did get the water on me and my hands, I thought that would be worth noting. Tweet