Superman55

I decided that this summer, I was going to drop some weight. At the beginning of the summer I was 240 Pounds, I am 6'3 tall, and right now I am 216 and have lost 24 pounds. However for the past week and a half or so, I haven't been able to lose at all. I have basically stayed at 216 and it wont budge. I was wondering if I have to wait it out? Or change my diet? Or exercise more? Currently I eat around 1500 Calories a day, and work out about an hour or so per day. (Mainly running, Crunches, and Push-Ups)