I can understand your concern, but it will be better if you post your symptoms first and then attach any reports like us reports etc.
normally, the volume of a prostate gland is 20-30ml.
also we need to know the size of the gland, post void volume and other details.
2mm calculus is a small calculus, it need not require any special medical efforts apart from pain management.
drink lots of water and you will be fine. make it a habit to drink at least 1 glass of water every hour and you will be fine.
avoid calculi causing foods like tomato, beets, chocolates, carbonated drinks etc.
consult a general surgeon for further help.
Dr. Anil Kumar J Jain