Can sex break your waters??

This might sound stupid but unfortunately I’m actually worried. So my boyfriend has a very big penis. He’s a bit bigger than 9 inches. I naturally have a lower cervix and now that I’m dilated I guess my cervix has lowered a bit? I don’t know this is what the doctor has told me. So we could never ever do doggy or anything like that because he always hits my cervix causing extreme pain. And when we do try doggy he gets too excited and accidentally goes all the way because he forgets. Which is fine lol but definitely ruins the mood and causes horrible pain. I’m about 3.5 cm dilated so we decided to have sex one last time just in case! Doggy was the only comfortable way to hold myself so we just went for it. Except it didn’t hurt! I didn’t feel him hit my cervix at all. So now I’m freaking out thinking maybe he went into my cervix?? And if he does “go into my cervix” could he possibly break my waters? I don’t want an infection so maybe we should not have sex? I’m sure his penis entering my cervix could cause an infection. Can this break my waters or cause an infection?