weight loss

So the beggining of my junior year of high school I was 140 pounds. I would eat anything and everything. This was in 2013. When I graduated high school in 2015, I weighed 120 pounds. I would only eat dinner mostly. And it would be a tiny amount. I'd drink Arizona tea every morning. When I came home last year from college I weighed 115 pounds. Since I started cosmetology school in July I have gained back almost 15 pounds. Is there anyway to lose weight again? I hardly eat over 1000 calories. I don't have time to excersise since I'm at school 9-5 pm standing. Come home, eat dinner, then fall asleep.