It is normal to feel post operative pain after implant placement. That can last a maximum of 3 months. Give it some more time, it will go away by itself. If the pain is still present after 3 months, then consult your dentist to check for nerve injury. If you are having acidity due to painkillers, apply Dentogel on the gums in the affected area. You can apply it up to 5 times in a day. After applying, remember not to wash your mouth, or eat or drink anything for the next half an hour.