What is happening!?

My son is 2 years old. I stopped breastfeeding when he was 8 months old. I was still producing trace amounts of what looked like colostrum after and was told that it was normal and could last for up to 2 years after breastfeeding. Well, for the past 5 days, my boobs have felt heavy, achy and sore and today, I almost started feeling engorged?? And now I'm actually leaking, a mic of milk and colostrum.... my so and I have been TTC for a month, and my period is due tomorrow. All the pregnancy tests I have taken have been negative, so I don't believe I'm pregnant... anyone have any idea what's happening??