Hmm at 14 weeks with a comb that large I'm leaning towards male. Silkie cockerels can take a long time before crowing sometimes (at 14 weeks most of my cockerels aren't crowing yet). If there are other males around and he is less dominant he may not crow or rarely crow as well. I've had some very early crowers but those often only do it a few times and then wait for months before regularly crowing.
I have seen females with some pretty large combs. Other than the comb and general stance there isn't anything I'm seeing that is definitely pointing out cockerel. I'm not seeing anything that looks like definite streamers yet which is what is confusing me. You never know you could have a very large combed pullet though I think it is more likely your silkie is a little cockerel. Sorry to not be able to be of more help, silkies are tough sometimes!