Getting fit/lean?

Voca_Star

I'm sorry for reposting this, honestly. But I haven't gotten a lot of advice so I don't know what to do. (

So two weeks ago when I weighed myself i was 141 pounds. Last weekend I was 138. This weekend I was 139.5.
I'm not stressing that anymore, weight fluctuates. I want to get down to about 115 - 120, hopefully by my 19th birthday, next February. By the way, I'm only 5'3". So I have a couple of questions and as many answers as possible would be greatly appreciated.....^^

First of all, I usually burn about 250 -400 with my exercise, depending on what it is. So should I eat those calories back or just stick with the 1500 that MFP recommends for me daily? I want to lose fat, so keeping a calorie deficit is a MUST. Will it still count as a calorie deficit if I eat my exercise calories back? I've spent the last month eating 1500 and haven't lost any.

Second of all, for exercise I do: Sun, Tues, Thurs, Friday, I do 35 - 45 minutes of intense cardio. Depending on what I do for cardio, it burns between 250 - 400 calories. And then on Monday and Wednesday, I do a circuit routine. This is my routine:

5 minutes of rope jumping
20 crunches
25 squats
10 - 15 (all I can do...for now) push ups)
5 minutes of running in place
25 leg lifts
15 lunges on each leg
25 chest flies (ten pound weights)
*****And, repeat. About, 3 - 4 times.******

Is this a good routine for losing fat? The cardio alone will burn about 300 - 400 calories (according to MFP)

Third, with doing all of this and keeping a diet high in protein, low in sugar, and eating lots of vegetables, fruits, whole grains, fat-free dairies, and drinking lots of water, will that be a good way to get a flat stomach? I have an event next May I want to look lean for so any advice is great!

Is it possible to get fairly lean by then?