I'm having pain in my right lower back. I had an ultrasound 2 days ago and they found an echogenic area on my right kidney. What could this indicate?

Need MRI or CT. Further evaluation is needed. This could be benign or malignant. Best study is MRI with contrast, although if lesion more than 2cm in size CT with contrast ( kidney mass protocol) is also useful. If lesion is enhancing ( has blood vessels) then urologist will decide treatment. If not enhancing it is benign.