Hello Dave
Yes we all get those days, weeks etc, especially if something is causing concern. My advice would be to ask to see a different GP and tell them how anxious you are. I doubt it is anything to worry about but I think we know our bodies best and we know if they aren't right. Let's be honest, it's not normal to have a dull feeling in ones stomach so what did she say it could be?
You could consider ringing the charity specialist nurses for a chat tomorrow, I'm sure they'd give you good advice.
Take care
Devonmaid