cold steel: Are these simply my imagination? Are they reflective anomolies of light and nothing more? Or are they images of the past?
Yes. They are reflective anomalies of light.
You had mentioned negatives. Analog film is only sensitive to the visible light spectrum (unless it is specialty film such as infared sensitive). If you cannot see something with your naked eye, neither can the camera - the film only records what is in the visible light spectrum. Any anomalies that the film captures are simply the result of optics...nothing more (*except chemical processes). And the interpretation of those anomalies are influenced by the phenomena described in the link Cofty provided