No worries. If it is this, the big danger is more from infection after removal. Let us know what happens.
Yeah I found out from only forum it is. I saw a pic of it and it looked just like it. Thank you for confirming it also! I was really worried.
It sounds like a horned growth (hard to be sure, not seeing it). Usually they get removed surgically or by laser, depending on the size. If this is the case, it's not especially dangerous to wait a few days to a week. But remember, not being able to see it, I can't swear to it.
Then again, if your vet won't allow you to be billed...there isn't much to do about it.
Except perhaps find a better vet. :)