Hi Jeddy, your symptoms sound so similar to mine and were close in age I'm 36 I have been dxed with Probable YOPD due to the neuro thinking it's genetic PD (Parkin mutation) I've had my bloods took 6 weeks ago waiting for results, from what I understand genetic pd is the same as idopatic pd just the know the cause is due to my genes.
Mine are all one sided (right) have extreme dystonia in my right hand and arm is affected due to my hand not working, I have a limp and slap my foot down and drag my right foot now and again due to not flexing up quick enough I also have no tremor... These symptoms close to yours?
How much Sinemet you on per day? I'm on 1 x 100/25 madopar 3x a day but I think I need the meds need increased they are working as my hand has about 50/60% movement/speed etc.
Sorry av rambled on abit just you sound so similar to me.
Trev