Backstory: I'm new to this site and I'm just trying the eat more to lose strategy. I lost a lot of weight in the past, but I did it by eating almost nothing and taking appetite suppressants and working out like a maniac. It made me really sick and I want to do it right this time because I gained most of it back pretty quickly when I had surgery that kept me in bed for a long time.

Problem: I exercise a lot just for my own mental health. I use a Polar heart rate monitor to keep track of my calories burned. I bike and walk every day and do resistance training 3 days a week. I usually end up burning between 800 and 1200 calories in exercise per day, but the rest of the day I just sit on my *kitten* playing video games. That may seem like a lot, but I have a considerable amount of free time and doing little spurts of activity 2-3x a day makes me happy and isn't overly strenuous. I tried eating around what it tells me to eat for this first week. Most days I don't quite make it and have 500-600 calories left. I try to be very accurate with measurements... I measure and weigh most of my food. At the end of the first week, I have gained weight. What the hell? Should I take this as a sign that MFP is giving me incorrect calorie requirements? Is there some sort of adjustment period if you choose to up your calorie intake? Sorta freaking out... help. T_T