So yesterday, I had a big new annoying floater in my right eye. Today, it seemed to have moved on, but there were an unusual number of floaters in the eye and I saw several unexplained flashes of light in that eye. Checking the Internet indicated that might be symptomatic of a retinal tear (which would be bad), so I called the hospital ER and asked if this was something I should come in for. They said yes, so the family headed in that direction -- since I might not have been able to drive home.
The nice doctor looked at it and didn't see any problems, even running a retinal ultrasound to double-check, although the last was more for the benefit of the resident who was observing.
So I'm to check in with my regular eye doctor next week, but it looks like we can call off the emergency.