Is is right that I am still experiencing pain after implant treatment three weeks ago?

Q. sir had 3 implants put in 3 weeks ago in lower jaw the farthest teeth back. the 2 farthest back feel fine the 1 closest to the front which seemed to have more lacerations from the surgery still hurts to the point where i have to take 800mg ibuprofen 2-3 times daily. though it seems to be getting slightly better slowly is 3 weeks a long time for there to be pain or is it just normal. i had the stitches taken out last week and the doctor said pain could exist for over a month just wanted a second opinion any info would be greatly appreciated thanks lloyd,