I have these too. Been going on for over 3 years...scared the crap out of me the first time..thought I was having a stroke. I lost pieces of my vision for over 30 minutes, followed by a short, but intense headache (less than 5 minutes) Been to several opth guys, and they found no mechanical failures. Finally went to a NeuroOpthamologist, and he declared that I have acephalgic migraines (migraine without the long-lasting devastating headache). I also sometimes see birght points of lights, for a few seconds and then they are gone. This is a type of floater I've been told.
Don't think the lights are related to BFS, but who knows? Been aware of my twitching for 2 months now, but may have been going on longer. By the way, the Neuro told me the number 1 trigger for migraines was stress. I notice I can get them more often when stresseed. Go figure!
Hang in there!