Diet help please, 135 pound female?

During winter break I tried an orange diet for a week and dropped from 148 to 135. I'm usually 115 - 120 but I gained tons of weight when I started birth control and I think also because I was eating unhealthy food living in the dorms since I didn't have a car first semester and ate what they sold on campus. I've been trying to lose the weight since jan. I'm 5'5, I'm 20 years old and I currently weigh 135. I do workout everyday for an hour and a half and for breakfast I eat a 1/2 cup of cherrios with 1% milk, for lunch I have light yogurt (110 cal) with 3 cut up strawberries and a banana cut up and for dinner I usually have a sandwich with swiss cheese (90 cal), wheat bread, a little light mayo, onions, and turkey. I was thinking of trying a carrot diet for a week, would it work as well as my orange diet?? And don't say this is unhealthy please I ate only oranges but I also took multivitamins, fiber, and protein for that week. To give you a look on my metabolism: I urinate probably 15 times a day and I do the other thing around 4 to 5 times a day. Advice please? Oh and the ten pounds I lost during winter break I know it wasn't just muscle cause I lost inches and looked skinnier in general.