Can you tell me where does the dentist stick the needle in your gums?

Varies: Different nerves travel in different areas of your mouth, so your dentist will insert the needle in the location where he wants to deposit the anesthetic for your specific procedure and the nerve(s) s/he wants to anesthetize. The pinch is minimal, and with topical gel placed first, almost unnoticeable.

Local anesthesia: This depends upon which tooth and the procedure performed. Generally for upper teeth: next to the tooth just above the tooth on the outside gums. For lower teeth: generally in the back of your mouth near the angle where your upper and lower teeth meet.