What Is The White Discharge Through Nipple After Discontinuing Birth Control?

Hi. I was on birth control pills and i stopped about 1 month ago. I was about to take a shower when I decided to check my nipples. I squeezed my left one and a dot of watery /milky discharge and I tried doing it to my right one and I didn't get anything. I haven't had any pain or weird symptoms can someone answer why I am getting this?