When did u apply for opt?It takes 3 month period for your process.You can also find out by logging to their website.I'm sure that u must have received some kind of letter from usics saying that they have received your application and 'll hear from them in 3 month .But usually it wont take long. They are not supposed to denied ur opt because it is your right to get your opt after graduating. My best advice is go to your intl student adviser and talk to them.GoodLuck.