Why Do I Feel So Bad About Breaking Up With Him?

okay so I'm 14 a freshman in high school and i met this guy who told me he was a senior  and 17. he asked me out the same day we met and i accepted. the next day, when i saw him at school he was acting really weird. he tried to make out with me, tried to meet me after school to do some things and he started following me all day. i have no idea how he figured out all of my classes when we met yesterday but there he was waiting for a hug and a kiss which i refused. so the next day i was all ready to break up with him because there he was waiting for me at the bus stop (i never told him i rode the bus) but then he apologized for moving a little too fast and he became the sweet guy i had known before. so i let the fact that he was still following me around thinking he may just be concern of my safety or whatever. needless to say, i didnt break up with him, until my mom told me i couldnt date until i was 16. so i was really disappointed until i told him and he became a total creep again. he looked like he was going to cry saying that he has lost all motivation to complete his senior year and then he got really pissed and said " i just get really crazy when i dont have someone to love". at this point i scared and freakin out because he has only known me for 3 days, so i quickly end the conversation and run away. so now im thinking back and i feel horrible because he seemed so excited to be dating me but at the same time he was creepy and way to clingy for a brand new relationship. can anyone help me figure out why i feel like this