When I bought my orandas they were about two inches long and had a full headgrowth already! Most people say that orandas won't grow any wen until they're three years old or so, but I'm pretty sure that's in some rare cases.
Anyway, if your oranda doesn't have a wen, it could be good posting a photo! That way we could determine if it is an oranda at all, or if it was just a mislabeled fantail

If you can't post photos, look for these things:
- Does your fish have kinda' wide and flat forehead and not particularly pointed nose?
- Is the back very round? Or just slightly arched?
- Is the body rather short?
- Does it have rather big, flowing fins?

Those are some basic "landmarks" to recognize an oranda You can also google it and look at photos of orandas and compare your fish to them!