I've had acne since i was 14, am now 21.

these days i don't get much zits unless i am very stressed or eating like crap. however when I do get a spot, no matter what happens it always leaves a red mark that lasts for months!

I never touch them at all. Even smaller ones will do this. Any inflammation or redness at all on the spot, and it will guarantee a red mark. As such, I have a lot of red marks but little actual acne, which is a very annoying predicament. The odd spot i get just adds up.

I could try fade them, but I would rather understand why this happens to me and not most people that get acne.

EDIT:

I also want to discuss my idea bout popping them. after a good 7 years of acne you kind learn how your body responds to things, like food, stress, chemicals, physical touch, etc.

for me, I have noticed that if i leave a big or moderate spot, It always leaves a DEEP mark, usually purple for about 10 months. though on the occasions where i accidentally popped them while in development.... early.... they always seemed to make a big mess at first, but leave a much, much less severe red mark after. It would go in weeks instead of months.

My theory is that by leaving it to get as inflamed as possible, the pimple gets more blood to it, and may cause more damage to the skin which leaves a worse red mark that takes longer to dissipate. the healing response is long. By poping it while inflammation is low and not much blood is present, you actually bypass that inflammation period which does damage and makes the blood trapped leaving a longer red mark.

The type of skin damage from an early pop is just like that on the other parts of your body... if you slightly grazed a hand or cut it.... normally it heals with no mark left in weeks. same idea here.