most of the time, about 80% of all, there is no identifiable and modifiable cause of calcium deposits and calcium stones in kidneys. it is due to some genetic defects in the kidney's handling of calcium.
only in 15-20 % patients we are able to find an abnormality in blood levels of calcium or the hormones affecting these levels and it can be treayed accordingly.
as a general precaution you have to drink a lot of liquids to keep your urine dilute like water throughout the day and should take citrous fruit juice like lemon or lime or a potassium citrate
syrup to prevent stone formation.
there is nothing very serious about it and in case there is a big stone causing obstruction it may need to be removed surgically which can also be done through a small hole these days easily.
so go and take appointment with your doctor .