Emma, I don't think you're doing anything wrong at all. 5'4" and 132 lbs. is not exactly obese. You are exercising regularly and being careful about what you eat. That's great. It's what everyone should do.

You say if you're being good, you average about 1300 calories/day. How often are you not being good? That could be your problem.

You're averaging 20-30 miles/week. You might lose more weight if you upped your mileage to 30-40, but can you sustain that level? If you do it for the short term and lose weight, you probably will regain the weight once your mileage goes back to 20.

I don't think anyone can ruin their metabolism. Your body will react to the demands you put upon it and the calories you consume in predictable ways. You may need to change the amount you exercise or eat to lower your weight, but that may not necessarily be the best thing for you.

Maintain a healthy lifestyle and don't worry about numbers.

Keep running and enjoying it. I wish I were as smart as you when I was 28.

You haven't ruined your metabolism, you are just not eating enough to maintain it.

It takes energy to burn fat. A lot of energy. More than twice as much energy as it takes to burn carbs or protein.

Calories = energy.

Try upping the calories to 1,800 a day for 6-8 weeks and see what happens.

You won't gain weight eating less than 2,100 calories a day.

There is not likely anything wrong with your metabolism. Your metabolism is the sum total of all your living processes. It is impossible to alter any aspect of your metabolism significantly and have it go unnoticed. The very first part of your metabolism to "slow down" under conditions of privation is your reproductive cycle and that does not go unnoticed. Virtually any significant change (except one) in your metabolism is very obvious and usually has a medical name since it is a condition that is not healthy.

The single (and only) aspect of your metabolism that you can easily change is your physical activity level. You can slow or speed your metabolism by altering the amount of exercise you get. Your body cannot "get used" to fewer calories nor can it "hoard" everything it gets. Darwin has guaranteed that we all fully utilize all the calories we get and waste none. There is simply no way to get more energy out of what we eat nor is it possible to hoard anything additional from normal. The normal condition is to extract 100% of the energy from food and to use or hoard everything. There is no room for improvement.

There is also not any difference in the weight or fat producing quality of any calorie. A calorie is a measure of energy. All calories are exactly the same in terms of their effect on weight. Certainly, some forms of calories are healthier than others, and some forms may affect your hunger in different ways and for different times, but all calories have exactly the same effect on weight.

The bottom line is that the ONLY thing that affects (fat) weight is the caloric balance equation. Eat more calories than you burn and you store the surplus as fat. Eat fewer calories than you burn and the shortage is made up from fat reserves.

The above may not be what you want to hear but any product that suggests it can ignore this fundamental is an outright scam. Stick with your careful measurements and Fitday. It will work eventually. Daily deviations from your "true" weight are common due to water retention etc.

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gotta run...

Keep up the consistency with running. Give it a couple more months. As we get older there is a very small but gradual decrease in our metabolic rate every year. Google it if you want exacts. Sounds like you are already doing a little weight training, which will help. NOT heavy weights (=bulk) just lighter weights with high reps. With school etc...and probably lack of adequate sleep, the body is in more of a stress state and may be holding on to some calories to protect you. You are healthy, focus on that for now. Good luck with school!

I agree with bigapplepie. You are definitely not eating enough calories. 1300 calories is fine on days that you don't run but on those days that you run, you need to eat those calories burned. So, if you run 5 miles and are figuring that is 500 calories, you should be eating 1800 calories for that day. Your body isn't getting enough fuel, so it is storing what you eat instead of burning it. You should eat frequent meals too which will also boost your metabolism. Once your body knows that you will not deprive it of energy (food), it will burn whatever you eat. Keep it healthy though. Include protein, complex carbs, and fat at each meal and have snacks in between meals. Strength training to build a little muscle will also boost your metabolism.

-There's plenty of time for rest when you're dead-