Pimple leaves birth mark?

I know that you shouldn't pop your pimples, but I unfortunately have been for a while. My problem is that when I do, and the spot is healing, I think blood dries underneath the healing skin and it leaves a small brown mark that looks like a tiny birth mark or freckle. I believe it's just a small blood spot or scab underneath the skin. Is there any way to get rid of them or prevent this (other than not popping my pimples).

If you look at the picture, all the small brown marks are leftover from zits. You can also see a fresh lesion near the top, and it has two brown marks inside it. If I leave it alone and let it heal, it will leave two more brown birth mark things. I've my face used to be clear, now it has the pimples and the brown marks it leaves afterwards.