Could I burn my skin with a 12% of glycolic acid?

Thank you for your question. 
If the glycolic acid is a moisturizer it’s possible to irritate the skin and turn red and flaky from use, especially if the skin is sensitive or has eczema. Some people do well though. If the glycolic is part of a peel, it must be a neutral pH or be neutralized after application. Speak to your Dermatologist and look at the instructions. 

Thanks for your question.  Any strength of glycolic acid can cause a burn if used in very sensitive skin, especially on the neck.  I would be very careful in the future using home peels.  It is usually a good idea to have an evaluation by a board certified dermatologist to help you determine  your particular skin type and which cosmetic procedures would be safest and most effective for you.
Best of luck!

Hello and thank you for your post. Unfortunately the skin and sebaceous gland distribution along your neck is different than around your face. The skin on the neck may be more sensitive as you have experienced. I would apply liberal amounts of vaselline, keep the area protected from the sun, and seek the evaluation of a board certified dermatologist to ensure that it will heal without any complications.
Best,
Dr. M-D.