Conditions that make your butt stink

Hey,
So I've had this weird problem that started back in 6 grade where I smelled a poop smell coming from my anus. This continued on for 2 years until I decided that I wanted to get rid of the smell so I looked up ways to get rid of the poop smell. I found a good way to get rid of it and it worked. This is the weird part. 2 weeks after "getting rid of the smell" I stunk up a whole classroom. Since then it's been smelling probably around half the time. I was just curious if anyone knew of any conditions that might cause this? Also based on my observations it seems thinking I smell keeps it from smelling but I'm not 100% sure about that yet Tweet