Hello kjammer21,
Your symptoms are an almost exact match to mine. I do see symptom exacerbation with excessive or increased activity. I also am basically seronegative on most standard bloodwork for typical rheumatologic conditions. I have had a UC diagnosis (18 mos ago) that is currently well managed with just mesalamine. While I cannot offer any input on causation as I am also seeking answers; I can offer that I will be meeting initially with internal medicine at Mayo in the coming weeks. Hopefully, they will be able to add to this conversation and provide some answers relating to underlying disease or condition so that possible healing avenues can be explored vs symptom management.