Your load weight of 35lbs ish is a pretty common weight, and perfectly fine and similar to my touring load.
but really, those are pretty darn high mileage days there dude. Riding loaded takes a hell of a lot more effort and you've got to work your legs into it.
Seriously, what you can do comfortably is really up to you, but the issues you describe are pretty classic over doing it.
listen to your body and next time adjust and have more realistic expectations based on what you learned this time.
but still have fun