Note there are "Registered" and "Trademark" that are not the same as "Copyright". The 45$ thing sounds like a rip off, and the .GOV adress doesn't help too much.
Basicly, the copyright is yours if you can provide evidence for your creation of the content.
Most industrialised nations have signed the most important agreements relating to copyright (Bern Convention) and neighbouring rights (Rome Convention).
To be able to prove your authorship you may also use a sealed envelope that you send to yourself, containing your content, keep it closed until you may have to open it under the eyes of a judge.
Or use a number of persons who can verify you're the creator. Basicly you only have to convince the judge.
Basicly, the copyright is yours if you can provide evidence for your creation of the content.
Most industrialised nations have signed the most important agreements relating to copyright (Bern Convention) and neighbouring rights (Rome Convention).
To be able to prove your authorship you may also use a sealed envelope that you send to yourself, containing your content, keep it closed until you may have to open it under the eyes of a judge.
Or use a number of persons who can verify you're the creator. Basicly you only have to convince the judge.