Had a tooth out today which is best painkiller I can take to help with pain and bruising?

Presumably no. Analgesic was prescribed by your doctor and if you are not allergic to any medications, then you can take 3 x 200mg Ibuprofen tablets every 6 hours to help. You can also take tylenol (acetaminophen) 325mg x2 alternating every 4-6 hours. Please consult with your doctor if you have any questions or concerns. Hope this helps.
Meds. Ice packs on and off for swelling and bruising. Anti inflammatories for pain ibuprofen. If severe, call doc for narcotic help.
Post surgical pain. Post surgical acute pain is biologically useful. Acute pain is of short duration, but it gradually resolves as the injured tissues heal. It is appropriate to use whatever medication (including narcotic analgesics) for treatment and palliation. Re.: follow your surgeon's directions.
Post-op info. I would assume that the dentist/oral surgeon who extracted the tooth should have given you post-op instructions on what you can and cannot do. Sometimes they provide a rx, but you should call them and ask. Some offices have particular preferences based upon the prodedure.