It is always possible to have symptoms. And you're correct in that everyone is different.
There haven't been any studies done on people in regard to this. There was one small study done with female athletes and lowferritin and there was a difference in their performance and oxygen levels. However, these women were really putting out effort and they were being measured by machines.
How this translates in the normal day-to-day functions of average women and their well-being, I just don't know.
The only real way to tell is for you to get your ferritin up (and you should do that with or without symptoms) and then you can come back and tell us.:D
I will say that I do feel better with a ferritinof 20 versus a ferritinof5.