I have a small white blister apeared a week ago between my front and back passage on outside skin near hairs. I am 76. I have diabetes (diet controlled) hace had cancer twice but this isnt hard or pea like. a little tender, possibly didnt notice straight away. Does it sound urgent........goldenoldie. I also have allergies and Asthma and Rhinitis and Blood pressure. so take quite a bit of medication. weeks ago had 0p for Sinus, nasal polyos, (FESS) is the leaflet they gave me.