That does not look good. I would have that checked out by a doctor ASAP! Given you've had this a long time and that it's gotten bigger indicates there could be something besides acne going on here. But I am not a doctor. Go get that checked out by someone who can properly diagnose your condition.

I had this acne since years ago, it was just a little black dot, and when I squeeze it out once in awhile (I know I shouldn't do that), there are these white stuffs come out, but the wound just won't heal by itself. Few months ago, I did the same thing again, but now this acne turned black and became bigger, I wonder what's that actually?

You REALLY need to have that looked at by a doctor. It may not be acne at all.

I agree with everyone else! It may be a mole that somehow got infected or something, which can be very dangerous. Go to a doctors ASAP!