MSK itself can't cause those symptoms I don't think BUT stones or gravel can. Constipation can be involved, too, as another symptom. I get that when I have an undiagnosed UTI going on .. or, need to drink more water.
I too have MSK. Diagnosed in 98. I have been suffering from the same symptom. I would get tailbone pain intermittently on the left side. It feels like I landed hard on something with my tailbone. It would even make my eyes water. This from a guy that has been passing a couple stones a month for over a decade (no tears). I spoke with many doctors about it. Nobody was really concerned. Lately, do to other health issues, my health care seems to have taken special interest in all my issues. I have acquired many new specialists. That really doesn't apply to you except they decided to look into that symptom by sending me to a Gastric Surgeon. Turns out that I have hemorrhoids up high. My surgeon banded one of them. They can only do one at a time. The pain came back. Not as strong as when it happens naturally. I think they're on to something!
SO GLAD you found an answer! WOW