I get really nervous when i have with my bf.?

We have been together for years and years but for some reason, probably my lack of self confidence I get nervous when we get frisky. Not so much as in i dont want him to see me naked or whatever but I dont kow if I am doing it right. When I go down south and he gets his, i dont know if I am supposed to keep going like that was just or is it over? Im not very dominant in bed so i dont want to just stop in the middle of it and jump on him but i want to make sure it leads to that at least sometimes anyways, i usually just stop once he finishes! Is that normal or do guys want after a bj even if they already got off?