Do u know reasons why u love someone?

i asked my bf threw text why he loves me btw he said "i love u first" a bunch of times b4 i said it bk and his answer was i dunno . so i texted okay and didnt text him bk for lk 2hrs and then i gave him an attitude when i finally did and i said u must not love me if u dont know why u do . and he said that he doesnt need to know why that he just does. ik why i love him.. and ever since that we have been argueing . who is right ? btw im 17 and hes 23