Drug-induced parkinsonism (DIP) usually affects both sides of the body equally, whereas idiopathic Parkinson's disease (PD) is almost always asymmetric, affecting one side of the body more than the other. In my case, I have PD with a resting tremors on my left side. It remained left side only for about seven years after my diagnosis. In the last year or so, I have noticed a random tremor in my right side, but the left is still the predominant side. My symptoms initially responded well to carbidopa levodopa.
Many forms of Parkinson's and parkinsonism's can be extremely difficult to diagnose, simply because they share so many symptoms making them virtually indistinguishable in the early stages.
The diagnosis of drug-induced parkinsonism syndrome is extremely important to recognize, especially in the initial diagnosis, as the syndrome is often reversible when the offending medication is removed.
The initial examination performed by both your primary care physician and your Neurologist should start off with a thorough investigation into all your medical and medication history to determine if your symptoms could be a reaction to any of your medications or the result of past medical issue. They have an extensive database listing all medications with all their known interactions at hand. So they should approach the initial diagnosis by adjusting medications to rule out any drug induced issues.
If you go to a doctor who doesn't start with checking medication interactions, reviewing your medical history, ruling out other diseases, etc. and simply runs you through the antiquated walk to the end of the hall, gets behind you and pulls backwards to see your reaction, had you tap your fingers, draw this squiggly line, etc testing. Your at the wrong doctor!

The neurologist should be able to go over your drug history and determine that, plus he might do a Datscan.

I agree but had to do that on my own. Have two siblings that are MDs that helped me eliminate medications that could be problematic.

I would ask my doctor first. I hope there is a way to figure that out for you.