Oak:
A little different, but the last time I did a "long" ride, my computer wasn't working (I think it was interference, because it was fine on the way back). The mile markers on the trail have worn off (they're painted directly on the trail), so I didn't know how far I'd gone until I got to an intersection. The sign on the other side said "Fort Ancient"...18 miles from home, and it was that first week of July, so 90s and sticky. I wasn't sure I could drive home from the trail head I'd parked at.
To make things worse, I had left my wallet at home. That was a fun drive...

Self:
This irrational fear of potholes is not helping anything. Most of our chosen routes do not have them in huge numbers, and those that are there are largely avoidable. If you really need to, you are allowed to get off and walk if you can do so without impeding traffic.
Go out and ride in an hour and a half and stop freaking out over every.possible.thing that could go wrong. It doesn't get anyone anywhere. Just enjoy yourself and your newly adjusted bike. (Besides, this may be the last time you get to ride as a "free woman." Enjoy it.)