My fitness plan, please answer?

I just joined Goodlife fitness center(in canada) and i just went for my first time today.

im 15. and im going to try to eat healthy, and me and my mom go there 2-3 times a week for about 2 hours(sometimes more)
I plan on going to the tredmill(fast walking) for 30 minutes, the recumbent bike for 30 minutes and the Elliptical Trainer for also 30 minutes.
i'm 160 pounds and 5'6. I want to get toner and tighter before summer, do you think this will work? how much weight do you think i will weigh before summer?

For some reason, i want to push myself to the limit, i want to lose weight NOW, i always try to over exercise.
Will i look "skinner" or "slimmer" by the summer? I want to give up sometimes cause i always think i will look fat forever.
How big of a change before the summer?

As long as you're watching what you eat you should be able to lose weight. Honestly I think you're starting out with too much. You are increasing your chances of injury, which will sideline you and you won't be able to exercise at all. I would start with an hour....sounds like you're at an hour and a half....cut out the last 30 minutes and spend that time doing weight training. If you want to look slim you have to tone the fat into muscle, which will happen some with cardio but not as much as if you do even light weight training. Do lunges, wall squats, and ab exercises. Also, if you can, swim at least once a week. Swimming is GREAT for cardio AND muscle tone.