I asked a friend, an anatomy/physiology professor about your problem, and he answered that while he's not a physician, it sounded like some swelling of the orbital globe or ocular muscles was involved. This wouldn't be surprising if you got hit in the eye but not badly enough to require emergency treatment.
It's a possibility you should ask your ophthalmologists about. One of the simple tests for this is that business where they hold up a finger and ask you to track on it as they move the finger from side to side. Was this done?
As to macular degeneration, it's a "When you hear hoofbeats (at least in this country) you don't start looking for a zebra" situation. If your three ophthalmologists looked at your retina, as they almost certainly did when examining your eyes, they would have specifically looked at the macula. That's a biggie. And of course macular degeneration is a disease of old age.
However, why not go back to them one more time and ask them about the possibility of slight swelling from the injury, and if they have looked at the macula?