Y'know, at this point, you might not want to spend the money for them -- depending on what the doctor does for you on Thursday, iron pills may or may not be what you need. If your iron is really really low, they'll probably give you an injection of it, because you'll need more than your stomach could handle.
You've had so much tension for so long, it may be just nerves that are causing your stomach to be upset. I know that happens to me frequently. Try eating some plain soda crackers and see if that helps settle it for you.
Just one more day until you can finally get some help!