You are 13 years old and still growing according to a recent post. Plus you are already close to a healthy weight, you should not be extreme anything. If you are not happy with your shape, strength training and other exercise could help. Also, you should eat more protein and fresh fruits and vegetables, not processed foods. 1800 cals would be a minimum intake, depending on your activity level, you might need to eat more. If you insist on trying to lose a few lbs, please do it in a healthy manner that is not going to damage your long term health and growth!
The side effects of allergy medications keep some people from using them. Natural remedies can be a great alternative, but some are more effective than others.