I don't know much about long distance cycling, but I do know you can easily overdo stuff like this and hurt yourself in the process. Pace yourself! Don't push yourself just because you want to and it feels good, do it because you know you're ready
On a trekking bike?? Holy sh.. respect - I expected that was made on a road bike with low to moderate stress (? Not sure about that word, not my mothertongue)
I disagree, if you feel good and you want to, keep pushing! Just make sure you get enough carbs, electrolytes, and water.
If things are hurting, look into bike fit. Your joints shouldn't be in pain. If you are feeling the "burn" then ease up or take a break, or learn to enjoy the suffering.