can i flash without unlocking bootloader? topic

Hi guys i just got my g3 here's what i did
*root phone using stump
*install superSU and clockwork
*install custom recovery using flashify
*flash twmp or whatever the recovery is

Now i have acess to flash roms but dont know if it is safe to do so because i never hooked up phone to computer to unlock the bootloader. The Rom i dkwnloaded was a (bump ) compatible Rom