Black spots in vision

[EyeChick924]

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. I was well hydrated and ate a couple hours before the incident. I did not feel abnormally light headed or dizzy. The black spots were my only symptom. The only thing I did differently in the last 24 hours was go on a very long run (yesterday). Should I be concerned?