Queef after sex; normal or???

So I noticed whenever my boyfriend and I finish the sex round I queef (when air comes out your vagina) a lot! It's happened with my previous boyfriend and I would cover it up with music playing or something. But last night was pretty quiet and I couldn't cover it up. He asked what that was and I had to explain sheepishly... I used to be so embarrassed by it but I'm coming to accept that it just happens. Is this normal? Does it happen to anyone else??