You shouldn't be so hard on yourself! Think of it this way, 6 tbs of peanut butter is far better than what you -could- be eating. (Large portions of fast food for instance.) Also, if you do something you didn't intend to do one day, you just need to move on. You're not going to gain 10 lbs overnight because you ate peanut butter. lol (Peanuts are considered a good fat, actually...) And besides, having some days that you eat more calories than others actually helps you ward off plateaus. Keeps your body guessing.
Don't stress it. Seriously, you're fine. No one is perfect, and if you spend all your time stressing about eating the exact right amount of calories, and beating yourself up when you do slip, you're not going to be very happy. Chances are, it'll be really difficult to keep up your diet too... you'll be more likely to get frustrated and quit.
Good luck. You'll be fine... keep up the great work!
