Cancelled Flight without a Mileage Plus account

I cancelled a flight in January and didn't have a mileage plus account. Thinking I have a credit from the cancellation, I tried to look it up using my last name and confirmation number but the united website said invalid confirmation code. I filled out the refund request form and they found the flight but said I'll need to wait a week or more for more information. Is this normal? Is there a chance I don't actually have a credit? I'd like to book a new flight asap but am wondering if I need to truly wait a week or more to find out if I have a credit. If it matters, the class of ticket I cancelled was United Economy (N)