I got extensions and my real hair is a bob hair cut and it stops at the back of my neck, and the extensions are half way down my back. What should I do to blend it in. Should I layer my extensions. Cut it myself?

You can layer your extensions to blend them--the stylist who put them in should probably have done this for you (try calling the salon and telling them you're unhappy with the job the stylist did; they may be willing to take care of it for free). Make an appointment with your stylist, tell them what happened and what you want. They'll be able to fix you up! :D