boobs making milk but not pregnant

this is the weirdest thing that’s ever happened to me but here we go. when my boyfriend and i are getting down to business we’re very rough and aggressive. he’s kind of obsessed with my boobs and like sucking on them and playing and stimulating, the works. and i really like it too so i’m not complaining. but the last time we had sex he was on top and grabbed them and something squirted out of both of them. like squirted squirted- like got DISTANCE. this has never happened to me before and now i’m super self conscious. he didn’t mind and didn’t make me feel bad but now i’m kind of nervous to let him stimulate me that way but it was one of my favorite things we do :( i know i’m not pregnant but idk... has this ever happened to anyone else? any tips?