Oh yeah, buying that bag of M&Ms and eating them will REALLY help.

Step away from the snack foods!
I remember your one slip with the cookies and cheese puffs. In my experience, a day like that won't make you gain weight, but it could stall your weight loss.
Sorry to hear you're having a rough time of it. Are you using a tracker, like FitDay? Are you measuring your foods?
Basal metabolism is the bare minimum of calories your body needs. Most trackers go by Resting Metabolic Rate. For example, at my age, my resting metabolic rate is about 1620. I'm sure yours is higher. For me to lose a pound a week, I would have to cut 500 cals a day, which would put me at 1120.

Well, that's too low. So, I really can't lose at that rate unless I exercise enough to raise my daily calorie burn.
In the past couple of weeks, I've been averaging 160 cals a day of exercise, and that brings my daily burn total to 1770. My food total has been 1460--I've been having trouble... Anyway, with that small a difference, I'm on track to have lost only 1-1/4 pounds. I want to get my calories lower than that; it's just that I'm struggling.
So, reevaluate! Figure out where your counts might be off. Look more closely at what you eat, and be sure to count everything.
No M&Ms!
Jay