Are the Laser Hair Removal Side Effects Permanent?

Seven months ago I went to a dermatologist for laser hair removal in my neck. Two days after I had blisters, and the skin became darker. I was worried and disappointed, it was worst than before! Till now, the skin is still dark and I noticed a discoloration as well. I think the laser was Alexandrite laser. I am using Retin A, and moisteriser. What concerns me most is the colour of my neck skin, is this temporary or something permanent? what can I do to reduce all this? Thanks