Maybe introduce toys to use during sex? Like a bullet vibrator to use on your clit.
I personally had a hard time orgasming with my bf for a long time because I couldn't clear my mind completely of thoughts. Once you get past that hump, and honestly relax, it becomes so much easier. Don't pay any attention to how long it's taking. Don't be afraid to direct him, better yet you could simply sit on his face and focus on your own pleasure: ride his face in any way that feels good. (Can be his d!ck, hand, leg too, whatever brings you more pleasure in the moment). Let it be an experience for YOU, ignoring him for the moment.