I put toothpaste on my pimple and it burnt my skin near the pimple. So now I have like a dark spot. How do you get rid of it?

Irritant Dermatitis. Using any toothpaste for your acne can cause more redness and irritation. Please don't ever do this to your nose, save the toothpaste for your teeth only. If the irritation persists more than 10 days, please get it evaluated by your GP or dermatologist.
Toothpaste. Never use toothpaste on your face to treat acne! The rare too many irritating chemicals in toothpaste that will hurt you. The dark spot will go away over time.