Flank pain for 3 years. Is also fine.

Iv been having dull back flank pain on both sides for 3 years. Initially i was diagnosed with a kidney stone. At that time I was using BCAA and Whey Protein for workout. I took some medication and iv been having regular scans since then, the scans no longer show any stone. Iv had CT KUB, US all the blood tests Creatinine, KFT, LFT, Urine tests. But the pain is there constant pain. Mostly its dull, felt more when I breathe in but sometimes when i take some medication i feel SHARP pain for 2-3 seconds, then it again becomes dull. Also this flank pain increases when I take Whey protein or have eggs. Iv been very stressed bcz f this situation. Kindly hit me with some ideas. Wats wrng with my body. Sometimes the pain is felt in groin area too and while passing urine... My urine is clear and I have no fever. Blood work is also fine.