Black specs in urine

I do not have a diagnosis. Has anyone experienced black flakes in their urine? It started months ago maybe a year. It was only every few weeks. Then every week. As of now its almost daily. Ive researched it and I'm afraid what it sounds like. I know its not a uti or kidney stones. I just completed a 24hr urine test last week as I already have Iga N and FSGS kidney disease. My appointment last week I brought some of the flakes and the Dr believes it to be blood. And when I try fishing some out of the toilet some crush up red. Ive taken pictures many times if anyone would like me to post one. It is urine in a toilet so just dont want to gross anyone out. But can post a pic. Im also just feeling ill with bladder, groin, pelvic, and flank pain that has increased as well. I have pain meds but not helping. Any help would be appreciated. I dont have insurance either Bottomline I'm down in hole scared of what I think it is. At 44 I became a grandfather and I turn 46 in June. He is the sweetest boy and I want to see him grow up. Thanks for listening