>>237723
The main thing is to relax, if you're both having fun and enjoying each other then don't get worked up in whether or not you're actually domming him or not
Talk with him, share what you both enjoy in and out of bed, but if you think he's submissive then start setting little rules or play games for fun. Tell him he's not to cum until he's asks you and you say he can, tease him a bit every time you talk (if he seems in the mood) until he asks, then have him ask politely and reward him by saying what a good boy he is, or how hot it is when he's subby. After you let him cum stay and chat some more, play some vidya or something, then before you go for the night tell him again how fun it was earlier and how well he did
If he really likes you and he's naturally submissive then probably all he wants is to please you and make you happy, so it's important that you tell him when he has. You'll do fine, good luck man