Is it inappropriate having a crush on a younger girl?

hello all – now i have this problem that i keep thinking of – im a high-school junior who’s going to turn 17 in February, and i have this huge crush on a seventh grader who’s going to become 13 in January. do you guys think this is inappropriate? she joined the school just this year but we’re on good talking terms and i cant be sure but i feel that the chemistry is there. i really want to take a chance and take things to the next level but i don’t want her friends to bully her and i don’t want people thinking that I’m a sicko either. truthfully I’m not totally head over heels for her because i have some strange fantasy – its because i just love her company and shes just so pretty being around her makes me really happy! what do you think guys – should i just let this go and pretend i never had feelings for her or should i follow my heart?