I have been experiencing tingling sensations that come and go on the left side of my body. particularly my left head and face for about four weeks.

Neuropathy: Nerve root irritation of the 5th cranial nerve will cause tingling, burning, pain and even numbness of the face . This may be due to infection sometimes viral as occurs in Herpes zoster(Shingles) or the nerve being trapped at its outlet/root If the whole of your left body is involved then it can not be a single nerve problem. You need to consult a Neurologist as soon as possible to examine you.