I have had a lump on my butt but very close to my anus for maybe 6 years. 5 years ago it became swellen and when I looked at it I seen a "head" like a pimple, squeezed it and yellow foul smelling chalky puss came out.... Left it alone til yesterday, years later and bam, happened again, only this time there was 4-5 different spots that the puss came from. Left it alone today til tonight and there was like a main "head" that squirted puss. so I be concerned, leave it or have it looked at?