This morning I stood up, bent over to pick up my purse, and all of a sudden I saw black spots for about 20 seconds. By the time I thought to check if it was in only one of my eyes it had pretty much gone away. I'm in optometry school so I went to the eye clinic a couple hours later and there is no sign of any retinal or vitreal issues. They chalked it up to blood pressure fluctuations. I'm 24 with normal blood pressure. The only thing I did differently in the last 24 hours was go on a very long run (yesterday). Should I be concerned?