Boyfriend saying I love you

So on the 8th it'll be 6 months at 4 months i told him that I have fallen for him. He hasn't said i love you or the same thing yet any reasons why. Could it be the circumstances we are in that my parents don't know about him because they'd have a cow so they can't know about him until I graduate ehich is when him and i are going to be a year. Also im 18 and he's 24