Transitioning from Breastfeeding

My son is 7 months old now. He has two teeth and eats baby food multiple times a day. I wasnt sure when to stop breastfeeding but I figured I'd just do it until either he doesnt want it anymore or I run out of milk. Well I think we have finally reached the point where my supply is running low. I know there are things I could do to produce more but I think it's time to let it go. The only thing I'm struggling with is it does make me sad. I cant exactly pinpoint why. I was wondering if any other moms have felt this way.