inner tremor with ET

I have been diagonosed with Essential Tremor and am set to have DBS surgery in a few weeks.  I have a concern - I have a great deal of inner tremor along with the shaking of my right hand/arm.  Here I am close to the surgery date and the internal tremor only seems to be increasing.  The internal tremor is centered in the chest and abdomen area. My heart has been checked, blood pressure, pulse, and have also been tested in detail for thyroid issues - all showing very good results. To the best of my knowledge I don't feel any stress out of the ordinary, even with the upcoming DBS surgery.

I have asked my neurologist if this somewhat elevated internal tremor is within normal parameters of ET. His response was; maybe we're looking at parkinsons instead.  Even though I have been through a myriad of drugs and tests.  Short term he has put me on Carbidopa.  Will we be able to tell in short order if it is ET or Parkinsons?  What to do?  Any advice. Should I postpone the surgery?  In the mean time I have had to put on hold much of my profession until after the surgery from the hand/arm shaking, and in that sense time is somewhat of the essence.   Incidentally, the medical staff I'm working with is with an extremely well recognized medical center, so I do trust the care that I'm getting.