Am I the only one who has experienced a touring bike handling badly with all the weight packed on the back? Could the bike be "wallowing" and OP working extra hard subconsciously to counter it? What effect would uneven (side-to-side) loading have over an extended period? Heck, how much more stress is there from carrying all the gear plus the kitchen sink? (I'm certainly no kind of expert about bikes or touring, and this is no kind of advice not to proceed as cautiously as possible and listen to what your body is trying to tell you.)