Chemical pleel

I had a client yesterday, and I performed a chemical peel on her. I followed the protocol. I only used two layers; on the first layer, the skin was perfectly fine. I let the peel sit for 1 minute as instructed. Then, I applied the second layer. When I applied the neutralizing solution, the client started to feel very irritated, and some white marks started to show. I stopped the treatment by applying a cold mask. She kept saying that she felt irritated. When she left the room, she only had one red area. But today, I followed up, and she sent me this picture. I don't know how I can help her and if this is normal.