You're still in high school. This means that, no matter how mature you feel, you are still young and naive. This will probably be the case until around the time you graduate from uni.
Please recognise this. Please know that whatever you think 'love' is now, isn't. Please know that high school is a time to have fun and run free with songbirds forged from rainbows, not to worry and tie yourself down with 'relationships' that wont amount to anything.
Once you realise this, and change your attitude accordingly, you will have a lot more fun. 'Youth is wasted on the young', as they say - I know I intend to enjoy mine.