发加急预约申请的传真给美国使馆(shanghai)HELP!

I will apply H4 visa to re-entry USA in Shanghai after vacation, however, the time of interview is too late. I have faxed the explanation to Shanghai USA embassy, but till now (near 4 days later) no body replies to me whether they permit or not. HOW CAN I DO? PLEASE HELP ME!

I just want to know the result they permit or not, why they can not call me?