This really ticked me off. To the point that the rest of the visit was ruined.
And that was your choice.
I think you already caught yourself in your last sentence.
I used to get in traffic jams on way to work, and have drivers do really mean stuff (easy to do when cut off from face to face relating to other humans) and I would get to work in a bad mood. Then a coworker told me I didn't have to let that ruin my day, or even one minute, and I realized how simple that advice was.
It is obvious you love and respect your Mom...and I'm sure it is out of love for you that she "worries". All parents are gonna worry about their children, even when they are not children anymore.
Being as close to losing my Mom as I am right now, due to advanced emphesema, there's not much (if anything) that I would allow to ruin even one nano-second with her.
Every moment is precious.......and borrowed time.