locked form won't unprotect

[Linda]

I created a document with text box fields. While working in
it, I could lock and unlock the document at will. Today
when I reopened it, the whole thing is protected and I
can't change the text on the page or enter anything in the
fields. I can't choose Tools: Unprotect because it's greyed
out. Is there any way to get back into this form again?

I used the "text form fields" in the Forms Toolbar first,
then decided to use the "text box" fields available in the
Control Toolbox that pops up when you click on Design Mode.
Is there a reason to use one over the other?

Thank you so much for any help.