I have a 2mm kidney stone this is the first one i have ever had in my life. will it hurt when i pass it through my pee?

Yes you will : 2mm stone most likely you will pass with out any intervention , some times you will have severe pain , along with small amount of blood in the urine , then you will be fine.

Calculus: Pain will likely occur as the stone passes through the ureter (the tube from kidney to bladder), causing partial obstruction. However, it has a 66 to 85% chance of spontaneous passage. A stone that small will likely pass from the bladder out the urethra (the tube from the bladder to the outside) with little to no pain.

Here are some...: In general, some 75-85% of stone < 4 mm will spontaneously pass through ureter to bladder with expected price of pain and suffering yet worthwhile in 2 wks; but it's not an absolute yes or no. Occasionally, a 5-7 mm may still pass and a 2-3 mm may cause a lot of problems requiring intervention. So, work closely with Doc so to individualize the care timely to earn the merits of medical care.