It sounds like a learning experience.
I would have been seriously complaining and turning around!
I've found with anything that has to do with camping, it is imperative to test things more than you think you need to. And, even my measly 5.2 mile commute to work with a sometimes very heavy pannier changes the equation for a lot of stuff, so I can imagine how riding with 2 packed panniers, elevation, heat, etc. would affect the ride.
I like camping and I like riding, but I don't think I would do well with this.