Becoming official?? Should I ask??

So me and this guy have been talking for a while. Hes a marine, I'm army. We talked before I joined the army for a while and then about 3 weeks ago started talking again. He asked me what i want out of the relationship and of course i told him i want longterm relationship. So we're on the same page. Last night we went on our first date and he ended up sleeping over cause he lives an hour away from me. Idk if I should ask him if we are like a couple or not. I'm scared to ask cause I dont want to ruin anything. Should I ask or just wait??