I've had a small raised scar on the side of my knee for well over a year, I thought it was a big bite that just healed badly. sometimes I pick at it or nick it while shaving which subconsciously makes me pick at it again and it makes it inflamed a bit. Then it'll heal over again. 
Then a few months ago I felt what I thought was just a tiny scab or scratched bit of dry skin behind my knee so I picked it off without even looking or thinking about it... and it's still there. It will heal then I'll nick it while shaving again and then it will scab over and re-heal.

The other day I thought I had a spot on my neck so I tried to pop it but didn't seem ready so I just left it. Now it's left a small raised bit of skin and a scab in the middle.

now I'm paranoid that either my skin is having trouble healing itself and leaving raised scars... or it's something worse.