Is intermittent tingling on two fingers and a pressure feeling on the tip of thumb on my left hand a sign of impending stroke or heart attack?

Possibly: This may be related to a nerve compression syndrome, but TIA or atypical angina need to be considered. See your doc to get it checked out.

Tingling: This is more than likely due to something in your neck irritating a sensory part of the nerve usually C6 or c7. If you are concerned about it you should see your family doctor. Signs of a stroke are usually more pronounced ie, facial weakness, arm weakness, speech disturbance, visual changes..