Should i tell him goodnight randomly!?

This boy and I have been texting a lot lately and i really like it cuz he can keep a convo going and its interesting and im like 100 percent myself! We havent actually met in person but i have known his twin sister since 4th (we are in 8th now) anyways i asked him what high school he is going to and he said the one im going to so i was like your my new best friend! so now i call him that all the time and we are planning onn hangin out this summer. i think we are going to be good friends....or more in hs. he has been onlinr on fb for a while now. i wanted him to chat me but he hasnt so before i get off should i just be like... "night bestfriend!(:" all randomly or what?