Is my boyfriend using his kid as an excuse to be sketchy

My boyfriend has one child and he has him full time. He's 15. I haven't finally met him and he doesn't seem to really put in any effort to get know me. I've tried. But he mainly just wants to be around my boyfriend is his super attached to his dad. My boyfriend just said he has had a hard life. Especially living with his mom. And all that's fine. But I'm wondering if I'm overthinking stuff. I've been staying the night at my boyfriend's house all week. Almost every night in the middle of the night his phone goes off. He says it's his son calling him from the bedroom and he will be right back and he's gone for an hour or more. I always ask was everything okay and he says yes. He doesn't ever tell me more than that. I'm probably way over thinking things. If he's truly helping his child or something that's fine and doesn't bother me. However is it normal for that to happen every night in the middle of the night and for him to be gone up there for an hour? Or is that sketch. He never elaborates with me because he says it's his kids business and doesn't wanna embarrass him. Honestly again I'm probably just overreacting and he's being a good dad.

Edit: Thx guys! I tend to overthink things. I have been cheated on in the past and I'm trying not to bring past stuff in my current relationship.