I have had a strange thing happen since April of this year. A little bit before a bowel movement, I get a weird adrenaline rush, my heart rate elevates, and I get dizzy and sometimes have a panic attack. Once I have the bowel movement, my heart rate almost immediately returns to normal and I feel cooler and more relaxed. The adrenaline still floats around in my body for a while, but after is so much calmer than before. This doesn't happen with every bowel movement, only some, and usually in the middle of the night. It's not caused by anxiety, but seems to be the other way around. My impending bowel movement causes anxiety and panic. Does anyone else have this happen? If so, do you know the science behind it?