Hello Welcome in H.C.M. I have gone through your query regarding painful small swelling at the posterior aspect og tragus which is painful on touch and you have on fever etc. As you said it appears as you have develped a boil over tragal area, this is a common site for boil in ear. Need not to worry but if you are diabetic than special care is requared otherwise you may do- 1- Apply 10% Icthymol glycerine locally with small cotton pack. 2- Tab paracetamol. 3- Antibiotic (preferably broad spectrum with anaerobic coverage). Probably above will solve your problem. Regards.