In addition to what mknauss said, add your pool information to your profile. It helps to know what type of pool you have (fiberglass, liner, gunite . . .) and what type of equipment you have (salt water chlorine generator, variable speed pump, sand or cartridge filter . . .).
I know you didn’t want to hear - get a test kit, but there is no better way for you to get on track in the most timely and cost effective manner.