what at my parents like this

I'm in high school it's my junior year I'm gonna be a senior next year I done everything for my parents since I'm the only child .they give me standards by saying you better pass your classes and not get in trouble,you are to young to go out with boys and other things .My friend just had a birthday party and I asked them if I can go and then never said anything to me .I Iove my parents but why to do they keep treating me like a child why won't they let me have a little freedom at least