Have A Inflamed, Red And Painful Cyst On Back For Several Years. Is It Sebaceous Cyst?

Question : Hello, I have had a cyst on my back for several years now. On occassion it would come inflammed and my wife would drain it with manual manipulation (squeezing it) . It has become larger over the last several months and now i notice that the head of this lump is not dark/black and very hard. On the bottom edge of the cyst , on the inferior periphery it seems in has become inflammed , red and painful.. The lump/cyst itself is not however, just uncomfortable due to the pressure of its increasing size.. It is about the diamter of a dime currently, with the black dark center. There is also a mole off to the side that is now red and inflammed as well.. Could this be a sebaceous cyst or something more serious?? Thanks..

Thank you so much for your intial reply to my query and the rapidity of a response. However, since my initial question, I have been able to take a picture of this area and examine it more closely. It seems to me that in fact there is a cyst ,as I mentioned , a sebaceous cyst as you say. However, just inferior to it, as I also menitoned is now a red swollen area that seems to have a white pustule head to it. I was wondering if this should be a cause for concern ? Also, the head on the cyst is dark almost black and rather hard. Is this normal as well?? I do have a picture I can send to you for further evaluation but I am not sure how I can attatch it to this message...I did not originally have the picture when I first wrote to you.
Thanks so much for your time.
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