This is most likely due to cervical spondylosis (arthritis of the neck or bone spur formation in the neck vertebrae) which is giving you neck pain and hand symptoms.
Following investigations would be required;
1) X-ray of the neck spine
2) MRI of the neck
Following measures would be helpful;
1) Neck care in the activities of daily living.
a) No working on computer for more than half an hour in a single stretch. Same for TV.
b) Monitors and televisions exactly in front (180 degrees).
c) Contour pillow: Should fill the hollow when lying on back or straight. Available over the counter.
2) Cervical Collar or Brace
3) Cervical traction
4) Anti-inflammatory analgesics like Ibuprofen
5) Some physicians do give narcotic analgesics, in which pain / tingling is quite significant.
6) Physical therapy: gradually increasing exercises from passive stretching to active against resistance regime.
7) Electrotherapy in the form of TENS, interferential and laser and ultrasound.
8) Hot fomentation
9) Local analgesic patch / ointment / spray
12) Chiropractic manipulation
You can consult following specialists;
c) MD in Physical medicine and rehabilitation
Your weight loss is not likely to be related to the neck problem and should be investigated initially by a complete blood count and complete metabolic profile. This would give the clues for the further work up.
Please feel free for your follow up questions.