I can understand the client not wanting to continue, for one thing he may have (wrongly) suspected that you were trying to work through a period by using a sponge or something.
I wouldn't be too upset about it: a lot of men don't realise how fragile the vagina can be, so a fingernail nick or rough fingering can cause bleeding, or the vagaries of the menstrual cycle, which means periods don't arrive like clockwork.