What is queefing?
Noises made by the vagina during intercourse.
Gas escaping through the vagina, makes a farting noise
No its something that women do naturally. Somehow air got trapped in vagina possibly during sex or exercise. Etc. Blowing air into a vagina is different. That is dangerous during pregnancy. Some people enjoy doing this to a woman during oral sex. So to answer ur question, NO, queefing isn't dangerous, every woman does it and its natural.
I don't know what country you're from but I assume that with fanny you mean vaginal. That is aka queefing and it's because the man pushes air into the vaginal canal with his penis and then when he pushes it in again the air is pressed out. This is very common and normal and has nothing to do with vaginal or penis size.