Can I get my daughter back? HELP?

Over the summer my teenage daughter would go out late some nights and come home late and she spent alot of nights at her friends houses. My mother got worried so she called DCF, they said that it wasn't that serious so a company that worked with DCF offered us counseling. My daughter didn't show up a couple times and I made a mistake and told them I couldn't control her. So, they said that either I give custody to someone else or we go to court and she might get sent away to a foster home. I didn't even want to take the chance so we went to court and i gave my sister-in-law full custody but people tell me now that DCF wouldn't have taken her to a foster home because it wasn't a serious situation, they just said that to scare me. Now she's living with my sister-in-law and I can rarely see her, and they won't let her spend any weekends with me. She doesn't want to be there and always begs me to come home. What are my rights? and can I get her back?