Boobs are weird

So I can tell exactly when I ovulate because my breasts swell and become very tender literally within a few hours. I'm now towards the end of my tww, 1 day before AF. Well this morning when I stood up out of bed, I had this draining sensation from the top of my breasts towards the bottom, almost like fluid moving downwards due to gravity. Like I said, the girls do usually swell, so it's probably just water retention, but it's never happened to me before. Does anyone else have this feeling?