There is a condition called Irritable Bowl Syndrome or IBS that some people have.  It is often linked to symptoms of anxiety.  You might look it up and try some of the suggestions that the websites have for it.  If I remember right, extra fiber is a helper in controlling symptoms.  If none of the suggestions for IBS work, you probably should see a doctor.  Plus, they have medications available that can help control your symptoms if you know for sure what you have.

Good luck.  My aunt had it and it is not fun.

This happens to me from time to time when I'm stressed. I guess because I've always been this way I don't really think much of it. That said, frequency could be an issue. Thankfully, I don't get stressed very often. If this was something that happened all the time then I would have to do something about it.

Does this happen any other time, like when you eat certain foods? It could be a sign of a intenstinal disorder like Crohn's Disease. I would get that checked out.

Charcoal tablet is my first aid for loose bowel movement or stomach problems.

I think the hormones that were released when you are nervous are the ones that is causing your stomach problem.