My pimple wont go away .... I'm a little concerned

It's been 5 years, and 5 years ago I got a pimple on the back of my left shoulder. I wasn't concerned about it because I always get pimples, but this pimple was different because after I popped it, it never went away. It was like it became part of my skin. My mom thought the pimple had just gotten bigger, so she tried using a sterilized needle to pick at the center and find if there was any puss inside, but there wasn't. It just hurt really bad and bled a lot. So since then, every now and then it'll be itchy. There's no redness or hotness over it, it just itches! Now its brown and the skin looks tight but its still the size of my thumb and pops out of my skin. I'm just concerned because I don't know what it is. Someone help!  

[Dr J Singh]

Hello,
From the symptoms the possibility of sebaceous cyst and a benign skin growth needs to be ruled out. Sebaceous cyst may occur anywhere on body but scalp, ears, back, face, and upper arm, are common sites for sebaceous cysts. Blocked sebaceous glands, swollen hair follicles and excessive testosterone production will cause such cysts.

I suggest you to get an evaluation done from a dermatologist and get the diagnosis confirmed.

It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.