You are the first person I've found with the exact same problem as me. It's the marijuana sadly. I've smoked for 2 years and this summer has been my first encounter with emitting a shit like smell. (I've probably smoked 75% of the summer, first summer smoking almost everyday) It's unbearable to see someone notice your smell, I've only had this problem for a month and I couldn't be more stressed out. This smell only occurs after I smoke. My close friends that I smoke with have noticed this horrible issue and it's insanely embarrassing. When I'm sober the smell doesn't come so it must be the weed making me emit this odor and be stressed out. Very ironic because smoking weed used to be very fun to do with friends, now it's torture. I'm going to take a break from smoking and try again after a good amount of time ( I advise you to do the same ) has passed to see if the smell comes back.