Low supply?

I hear ladies talk about feeling full and leaking and engorgement. I have a 4 month old who is exclusively breastfed and the only time my breasts were hard and heavy were the initial few days/week back from the hospital after her birth. I could never press my breasts and hv milk come out. Can't hand express basically. Does that mean my supply is low? I know the supply regulates once feeding is established but I can't seem to press n hv milk drops nor do I have any full/hard feelings in my breasts. Are u all able to press and hv milk come out??