As to being cold all the time, that's very normal. I think most of us who have lost any significant quantity of weight complain of that same issue. Learn to dress in layers, and keep the electric blanket ready on your bed
About the junk food, perhaps you're not eating enough calories; or perhaps you should try quitting junk completely rather than including "moderate" quantities of it in your diet (many of us are not able to be "moderate" at all about certain foods which are sure diet killers); or perhaps you should figure out why you're wanting the junk and fix the cause.