The bruising highlights one of those really cool anatomy lessons. There are little fascial bands in different places in your body. Fluid will pool up against these bands and fluid does respond to gravity. This is why black eyes have that round, sharp demarcation to them. You'll even see this in people who have hit their foreheads and gotten bruises. After some time the bruising runs down and collects in the lower lids (not in everyone). You had surgery on your lids and the swelling runs downhill and pools up against the fascial connections. It will eventually go away. Some people heal faster than others. Try not to worry too much and if you have more questions about it go back to see your surgeon.The human body is fabulous. I encourage you to learn more about anatomy, health, and medicine. It is truly beautiful and inspiring.