My entire r jaw and back of neck is swollen n painful. low grade fever, excess mucus n phglem. hard mass in r jaw leading up into r nostril. any idea?

Emergency: You need to be seen asap by a dentist, oral surgeon or ENT doctor. Go now, do not pass go, do not stop to collect $. This may well be the onset of severe infection which can progress very rapidly and be potentially fatal. Hope this is managed promptly and you get better soon. Good luck. If you don't have $ go to an er and be seen.