It used to be that bombs, unlike guns, could hit friendlies without any killshooter damage being done to you. So I think the OP is asking did they change that feature. I think the answer is no, as having a bomb hit his bombers would certainly have done damage and he had none. I think they probably added the "you shot yourself" i.e. "you just shot a friendly" message without thinking that the same message will come up when bombing, even though there are no consequences.
