What you are experiencing are "olfactory hallucinations". I had exactly the same thing 15 years before I was officially diagnosed with PD. After these episodes, which were so disturbing, because they were always powerful and noxious types of odors, and then I lost my sense of smell completely. I was not officially diagnosed with PD until 4 years ago. Prior to that I had alot of non-motor symptoms, like "olfactory hallucinations", urinary incontinence, chronic insomnia, severe anxiety - my motor symptoms started many years later. Loss of smell is a major bio-marker for PD. My sense of smell has come back about 25% over the past few years. Please speak to your Neurologist about this...sorry I don't have better news for you.

Lexie