In my opinion, I would recommend against senna and would recommend a better laxative like Miralax if you decide to use a laxative.
I found a good laxative recently - liquid senna, and it tastes good. Also, mucous could be wormish - try catching in a strainer.
Im a nurse and totally agree with penn state.
Welcome to the gastroenterology community! It sounds like you are constipated. I would recommend increasing your intake of fiber, your intake of fruits and vegetables, your intake of water, and try to get more exercise. If this doesn't help I would recommend seeing your doctor and possibly starting on a mild laxative.