Eating 3,000 to maintain?

I am finally going into maintenence and I am wondering how many calories I will need to stay at my current weight. I know most teens need 2,200, but I also run for about an hour a day at 6mph (400 calories), lift weights for 30 minutes (50), and swim most days (300), so would that mean that I need about 3,000 calories? I am currently eating this amount, coming off of gaining, but after I started exercising like this my weight gain was much slower, if not completely halted. Does 3,000 seem unreasonable? I've seen a lot of other active teens on here who say they eat less to maintain. I'm really afraid that if I cut down on exercise and then cut down on food a little (since it's sometimes uncomfortable to eat so much) that I will lose weight and slow my metabolism. Can anyone help me out with this?

Also, when I was trying to gain weight, I'd have a 600 calorie breakfast, two 400 calorie snacks (morning and afternoon), a 550 calorie lunch and dinner, and then a 450 calorie snack before bed - which was usually eaten at about 11pm! Is it bad that I am eating so late at night? Should I just increase somewhere else so that I can downsize this snack? I am so confused right now. Maintaining is hard to understand, but I really don't want to mess myself up and lose weight again!

Well, if you don't lose weight on 3000 or don't gain, it's your maintainence. duh.

Logically, if you reduce your exercise, your intake will lower as it properly adjusts.

Eating more calorically dense foods can help make the 3000 not so daunting, though at your activity level (and age) counting really shouldn't be necessary.

Also, what are you trying to gain with your running and swimming? Especially the running, if you're trying to build speed/endurance, running 6mph every day isn't going to do much. Interval training, sprints, hill work is much more effective. It's also quite hard on the body to run every single day. 

I'm not sure of what your weight training regimen is.  30 minutes of fairly hard lifting where you alternate daily workouts and take a day off here and there should continue to build muscles which might instil weight gain.  However, since the body burns more calories to rebuild muscles, most people can build muscle but still maintain a desired weight.  Frankly, since you are so active and seem to be aware of how many calories you need, I think 3000 would be the minimum you need.  I am much older and although I do exercise around 2-3 hours a day, I do my exercise pretty moderately or even light at times.  I am taking in around 2900 calories the last 2 weeks or so and have maintained.  I am thinking at your age and if your metabolism is normal for your activity level, 3000 would be the least amount you would want.  Eat a high protein but healthy breakfast.  Space out 6 meals during the day and include fruits and vegetables along with nuts like walnuts and almonds in your diet.  Eat a lot of fiber foods like beans and whole wheat pasta.  Include poultry, lean pork and beef, seafood like halibut, salmon, and scallops, etc.  There are many recipes on the Net for healthy protein shakes/drinks that are high in healthy calories. 

When my brother was in high school, he had a hard time maintaining weight -- he ate a TON OF WHOLE-WHEAT PASTA, which seemed to help...

Also, I don't know what kinds of fruits/veggies you're eating, but I have a feeling if you look at the lists of "don'ts" on this site for dieters, you should just add more of those and less low-density stuff. (Carrots, corn, sweet potatoes, bananas... that sort of thing is all higher in calories but still really good for you.)

people recovering from anorexia usually have higher calorie needs after they are weight restored anway- there have been studies done and patients needed on average around 400-500 calories more than would have been expected post-gain (for about a year I think?) So given that, plus your age and activity level, 3000 seems reasonable- maybe even a little low but it's a trial/error thing. Remember that the usual calculators don't really apply for people recovering from malnutrition because even after target weight is reached, internal damage is still being repaired which is why calorie need are higher.