Liquid out of my boob

So for more than a month I have squeezed my nipple and liquid comes out . Not too much but  a dot or
Two. My friend is pregnant I asked her if she's lactating she said no next day she called me saying I'm lactating now . ( she was at my house when I asked her) I am not pregnant I've gotten my period. I've taken test and it comes out negative.  My partner and I are trying. But I'm curious to know if that's part of ovulating or could it be a health problem.