Sounds to me like hypnopompic hallucinations, basically hallucinations that occur during the transition from sleep to wakefulness. The opposite is Hypnogogic hallucinations which occur as a person makes the transition from wakefulness to sleep.
They're actually quite common, around 12% of the population has had experiences hypnopompic hallucinations and up to 40% has experienced hypnogogic hallucinations.
http://www.medterms.com/script/main/...ticlekey=24173
http://www.patient.co.uk/doctor/Hypn...ucinations.htm
http://books.google.co.uk/books?id=1...ations&f=false
http://books.google.co.uk/books?id=q...ations&f=false (page 253 right hand corner - page 254)
They're not a sign of psychosis. It's not really anything to worry about and not usually something that would be treated by a mental health specialist such as a psychiatrist, it's more in the realm of doctors who deal with sleep disorders hence why your psychiatrist may have been dismissive.
These kinds of hallucinations sometimes also co-exist with the condition commonly referred to as sleep paralysis, although since you didn't mention being unable to move when awakening I'll assume that you don't have that :P They can sometimes be a side effect of antidepressant medication either during the initial stages of settling on it or during withdrawal. But they can also be triggered by anxiety disorders, depression, bipolar disorder, narcolepsy, etc.
Hope my post has been of some help, just to reassure though they're nothing to be worried about :)
I experience similar things to what you described, odd hallucinations just after waking up from a dream or nightmare (insects, floating balls, etc). Hence why when I read your description I knew exactly what it was straight away. Unfortunately there's not much information available on the subject though really. So it's understandable that your searches on google didn't find anything. Unless you know the specific name for it, nothing tends to come up!