Leona, I totally want to see a picture of this!! But I also think that if it is what you suspect it might be--an umbilical hernia that attached to something else--that is definitely something that they should keep an eye on during your pregnancy. Maybe you can call and ask that your next appointment is with an experienced midwife because you have some questions?
Keep us posted, girl, I hope it doesn't end up being anything problematic (I think you've had enough of that this pregnancy, don't you?)!
I agree with Adrienne, I might just call and talk to the nurse and see what she says, otherwise I would call and make sure at your next appointment you have the more experienced one so you can discuss with her.
I hope it's nothing, I don't think mine has moved or anything, but I haven't been paying all that much attention to it either. (((HUGS)))