Bilateral calculi meaning both sided small renal stones detected in the scan. Stone may or may not  cause pain,may cause infection and may derange the function of affected kidney if obstructed. Get a functional study like IVP or CT Urography to look for functional aspect. Mixture of potassium magnesium citrate mixed with glass of water thrice daily in doses of 15 ml every time helps in both treatment & prevention. Consult a urologist for detailed clinical