Thanks for asking for help.
You don't have to panic here.
Please drink sufficient liquids atleast 3 liters per day.
If you have any urinary symptoms get a Urine- Culture test done & treat the infection if found.
The cortical cysts need not be feared . You can repeat the Ultra sound
scan after 3-6 months & see if there is any change / increase in size of the cysts. If yes get it attended to by an Uro-Surgeon.