dark/red urine can have many reasons. Infection!? Rupturing of small blood vessels…
Everything that damages muscle tissue is a part of rhabdomyolysis. So ME is a contributing factor. But why would you do it so short before a goal event?!? “sore for 4 days” is an indication that you did good muscle damage.
Your physician should know what lab work to perform, to check your kidney and muscels.
Have a quick recovery and be carefull with NSAIDs!