Longhorn
I wouldn't pack a restricted, if your eating crisps ( I don't know the carbs in those) but you can't have to packets for lunch. Why not pack your veggies, crisps and a salad? Never skip your bedtime snack and never move it into a different position in the day, it's very important for you to have that before bed. Dont forget to pack or plan on buying bottled water.
Your chicken you had yesterday will be ok, but we don't know if it had an marinade on it, but I wouldn't stress about it.
If you get those hungry pains, do not give in to them. Drink more water, eat another salad or make a cup of herbal hot tea.
Hope this helps! Best of luck to ya... GO ROCKIES!!!!