I fully agree that the burnt marks are likely to be due to irritation from the home remedy. Very often, certain products or home remedies can cause excessive irritation of the skin and this can lead to redness, inflammation and sometimes crusting of the skin, which often resolves with post inflammatory hyperpigmention. It is best to stop the treatment to prevent things from getting worse.
It is unusual for the acne lesion to turn into a mole. This needs to examined before we can advice further.
It is best to see a dermatologist/ doctor to help manage your skin issues.