Lose 20lbs before April 2nd!

Hey y'all. My birthday is March 29th and I am turning 21! My friends and I are all going out to dinner and clubbing and I want to look HOT! I weigh about 160lbs right now, and I'm 5'7"-I have a flat stomach and everything--I just want to lose weight in my thighs, butt, arms, and chin. I know you can't "spot reduce" so I'm asking how I can lose this 20 pounds. I am a college student-I try to eat healthy and workout when possible. But all I have to workout with is a yoga ball. And I am a broke college student so I can't afford any fancy equipment or a gym membership.

And if y'all don't think I eat healthy, I do. Today, for example, I had a banana and diet cranberry juice for breakfast. For lunch I had a turkey sandwich with white bread, lettuce, turkey, margarine, and mild cheddar cheese and a no calorie brisk iced tea, and for dinner I am having whole grain spaghetti. am I doing the right dieting things?

What else can I do to lose this weight?
Lose 20lbs before April 2nd!
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