Left Arm Pain with hand asleep

I am a woman, 5ft. 5, weighing 150 lbs. On September 4th I woke up with pain shooting down my left arm and my left hand asleep, with 'pins and needles' in all 5 of my fingertips.  I also had pain behind my left shoulder blade around T4-T6.
My general practitioner sent me to the hospital (to rule out a stroke). Once there they performed chest and neck xrays, KAT scan of head and neck, and EKG.  Everything turned out fine. (Blood Pressure slightly elevated, but went down before I left.)
Next, I had an EMG of left arm and left side of neck, with normal results.  Next was a MRI of cervix, followed by MRI of spine.  All normal with slight arthritis in neck.
I have been to my chiropractor 5 times for corrections and I am in my 4th week of physical therapy, but all symptoms remain the same.  Condition worsens when I'm slouching or tired.  Pain shoots down my arm and stops at elbow, but fingertips are consistantly asleep.  
My doctor is now requesting vascular tests to be done.  I am confused by this because my hand is still warm and I do have all my strength and feeling.  What else can be done to solve this mystery?  I am right handed and I do not do any repetitive movements with my hands or wrists, to cause this.  The only thing I did, out of the ordinary, was work temporarily with a Sawsall to cut 2x6's, under a trailor, for a missionary project.  I was working in cramped quarters with bolders under my head, and had to hold the electrical sawsall at a funny angle in my left arm, pressing it against my left shoulder, for support. However, this was all done the first week of July. I had knots in my shoulder after that and a little stiff neck, (all to be expected after sleeping on hard uncomfortable matresses), but didn't wake up with the pain and numbness until September. Could the two still be connected somehow?