Help with fittness?

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?



thanks for your help!

ALSO: i have gym 4th period, and i usually walk home(30 minute walk ) going up a big hill.

Well, it's a fitness center. I think it would be best if you talked to a personal trainer for a few minutes. Maybe they could recommend a routine for you. There is a reason why they get paid so much money and get a degree in fitness you know...:)

But I would cut back on the cardio a bit. Maybe just do 1 hour of cardio 3x a week. Then maybe through in some weight training for 20-30 minutes. You're not going to get bulky if you keep the weight low. You want to aim for a weight where you can lift it about 20 times.

Look around, there must we girls who are doing weights. That will help keep your muscle and muscle burns fat for nothing..just for being there.