The diagnosis of Stage 3 chronic kidney disease (CKD) requires two separate tests with an estimated glomerular filtration rate (eGFR) of less than 60 milliliters per minute per 1.73 meters squared and these tests should be at least three months apart. A urine test that shows blood protein or infection can act to confirm the diagnosis of CKD. Hence, you may need further testing in order to confirm the diagnosis of CKD.
The treatment of CKD first requires a specific diagnosis in order to determine the specific treatment. Once you have CKD, then the goal is to prevent further damage to the kidneys. You should have a normal blood pressure of less than 130/80. You should not smoke. If you have diabetes, then this should be carefully controlled.
It sounds like you are doing most everything you can do to live a healthy lifestyle. The ultrasound that you mentioned can help to evaluate the kidneys for reversible kidney disease such as blockage or other acquired kidney disease.
I do not have any other suggestions about treatment based on the information that you present.