I'm a 15 year old girl who is 5'3 and weighs around 130. I want to tone my body because I think my butt is waaay too big is it okay if I lose some weight?

To answer this question i need to know if your talking about weight in pounds or kgs if your talking about pounds as i assume this is your answer

For pounds you are at the end of the average section so you could lose a couple without harming yourself as long as you do it by regular exercise and healthy eating.