You have not mentioned whether it was the upper tooth or the lower as in case of upper back tooth chances of sinus infection after extraction is there but very rare in case of simple extraction. if you are taking antibiotics then it will take care of any infection, if it is there. you can visit the dentist and get the checkup done. Normally the dull pain can be there for 2 to 3 weeks but there should not be any fever.you should do warm saline rinses 2 to 3 times a day. it helps in healng. If you want to know more about the dental topics yu can browse our web site.