I was hold heavy grocery bags abd my finger tip got numb. its been numb for 4 days should i go to a doctor?

Yes, you may: have to. Prolonged neurological symptoms such as what you describe may need a good history, physical examination and some tests possibly. In the meantime try not to provoke any symptoms and try to to rest the are a as much as possible. Hope this helps.

Maybe not yet: If the only fingers that are numb are those that were pulled tightly by the grocery bags, the cause is almost certainly the constriction of digital nerves by the weight. Most likely you will have a complete recovery of sensation in the fingers. I've had the very same thing happen to me (years ago)! I believe my numbness lasted for 1-2 weeks. If you see no improvement after 2 weeks, I'd get checked