Just started lactating?

so this is my first pregnancy and im 27 wks 3 days. well on my way to my mom's this morning my shirt felt wet all of a sudden and of course it was the day I decided not to put a bra on until I have to because we're going on a road trip. then about ten minutes later I felt the same thing on the other side. so two small wet spots over both of my nipples. my mom said she's surprised it happened this early, not even being in the third trimester yet. has anyone else experienced it this early? any tips? I honestly have no idea what to expect when it comes to lactation and such. my mom couldn't breast feed me because I wad two months premature ado she doesn't know much either. help. haha