Sounds like you have a hard time putting things into words. You want to ask what's going on but are having a hard time with how to ask so it sounds right.
And you don't want to vent either... nobody does, but sometimes you have to, need to. Don't feel badly about that. Type it all out and delete it if you can't press submit, but at least type it out. Or pm somebody you trust, okay? It's normal to worry and goodness knows we get too little normal around here!
Good luck with the doc.