I need help losing weight?

I'm 17, 5'5", and 183 lbs. I'm pretty big and I'm trying to lose the weight. I drink mostly water and green tea, staying away from soda and surgery drinks. I'm not a big fan a sports, so to stay active I have a gym membership. I stated at 190 lbs and went down to 183 lbs but I have not been losing any more weight for awhile now. My routine is 30 squats on 30lbs, 90 calf raises on 25lbs, 30 bench presses 30lbs, and I lift wights to help my biceps. Then I repeat this again. Then I go on the elliptical for 20-30 mins. I do this 3 times a week. My question is; what should I do to too lose weight faster? And how long should It take. Any suggestions should be much appreciated.