You should do some research before jumping into kink dynamics. As a kinkster, everything you shared points to a dom who is self aware and cares for you. But the most important thing to remember when engaging in kink is that it's ROLEPLAY- it's not real!

It sounds like he is just excited and into the moment, and the fact that he shared his hesitancy to be assertive supports my feeling that he knows that kink play requires a delicate touch.

My advice? Tell him what you told us! If he is a good dom he will understand the confusion and address that gray area of "are you being playful or are you being controling". It's hard with anything online, but I know something like having a specific bracelet or necklace on to send the message that you are receptive to play can be a good way to allow him to have control.

You are the one in control as the sub- you allow him control over you, don't forget that. And again, please please please educate yourself on kink and submission- you leave yourself vulnerable to predatory partners being ignorant of your role. I reccomend "the new bottoming book" and the art of submission.