Nipple leaking - need advice

I had a baby 15 months ago. Stopped breastfeeding 4 months after he was born bc I had to go back to work and he wouldn’t take from me.

Anyways. Every now and then I check to see if I still have milk left and I do. Just very little.

Today I checked and a little bit of brown liquid and milk came out of my right nipple. My left had milk come out. I did a beast check on myself and didn’t feel any lumps.

I’m going to call the doctor Monday of course but has anyone experienced this??