I recently moved and I'm pretty sure my mail is being forwarded to my new house, but how long does it take?

I recently moved and I think my parents told USPS to forward all mail to our new address. I'm currently awaiting a money order and the guy sent it to my old address, how long would it take for it to be forwarded to my new address? and is there anything I can do to obtain it ASAP? like going to the post office if it's there?I recently moved and I'm pretty sure my mail is being forwarded to my new house, but how long does it take?
For me it took about an extra 3 days. I would call or go down there if it is urgent, but they may not can actually give you the mail but maybe they can tell you if it in transit to your new address.