hitting it from the back.. and i made a noise?

so my bf was hitting from the back and i was bending over and i made a noise almost like a fart but it wasnt bc i would n e v e r and i would of felt it so i wouldnt be asking.. was it a queef? my friend thinks its bc i was really wet and when he went in it made that noise but idk. we just ignored it but idk what it was