How early can you start lactating?

I had two days of spotting the day of and the day after ovulation. I have been moody, super fatigued, quick to tears, and some nausea. However, my period isn't due until the last day of this month so I figured it was all due to the things. Then today when I was changing I noticed my areolas seemed large with bumps and I noticed droplets of liquid on the nipples. It was clear and sticky. Am I lactating and if so could it be I am pregnant or is this way to early for that to happen? Please help!! I have PCOS and the started me on Metformin and I had my first regular period and first positive ovulation test this month and I am worried I am reading into things.