Eat right before you go to bed, Metabolic Drive or cottage cheese, preferably. People say to avoid carbs at night, but in your case, it may be beneficial.
Also, if you're drinking shakes throughout the day, make sure its got carbs in it. Then, add PB or olive oil to it.
You dont really have to worry about eating clean at this point, if you can get more calories in clean, good, if you cant, dirty eating can be your friend.
Read about how JB gained his weight... he says "If I'm not eating, I'm not getting bigger" or something to that extent. Its true. He said everymorning he would buy half a dozen cinnamon raisen bagels, put natty PB on it, and then take a gallon jug of water, and put 5 protein shake scoops in that. He'd eat these between "meals."
I suggest giving something this a try. Doesnt necessarily have to be this, but carry a shake and a big bag of walnuts around. Shit, eat a walnut every 5 minutes between meals and by the end of the day it'll be a fuckload more calories.
I understand you say its your appetite more than not knowing how to add calories, but I suggest adding right before bed.