Is there anything wrong with my workout?

I was in Circuit Training at my high school and I chose the weight lifting sheet. So, I did more weight lifting. It was great! I was more toned, had more strength and was more self confident. But, weights alone won't help you lose weight fast. I'd put in some aerobic exercise. (Rowing, bikes, treadmill, stair-stepper). And for the weight gain, it may bw the lack of aerobic exercise OR keep in mind that muscle does weigh 2x more than fat. Hope this helps!