All right, she has said this. it is now up to her to help you get it right. So contact her and say you need her to help you get it right. Get her to show you how to place him on correctly. You may need to change your position while feeding.
It's not to late and he will learn to attach with some advice.

Someone will be on to give you some tips as it's hard for me to remember how I was taught to get proper attachment.