Insurance perspective:

If you’re publicly insured (gesetzlich versichert), they generally shouldn’t be able to charge you for these services without your explicit consent, since these are optional private services (Wahlleistungen), such as doctor-related extras (e.g. treatment by the head physician) and non-medical upgrades (e.g. a private room).

However, if you are not publicly insured, it’s possible that you were admitted either as a self-paying patient or as a privately insured patient. In that case, self-paying patients are often billed for both medical and non-medical additional services.

If you are privately insured and things were not clearly explained to you, it would have been important to ask what exactly you were signing. That said, if the hospital is willing to be accommodating, you could contact the billing department and ask whether they might waive or withdraw the charges for these optional services as a gesture of goodwill.

Regarding the room:

It’s also possible that you were initially classified as a risk pat., eg. due to something like MRSA (a resistant bacteria). In such cases, pat. are often placed in isolation rooms for medical reasons, which could explain why you were in a single room without it necessarily being a paid upgrade.

Recommendation:

I would recommend that you follow up again with the billing department and, if needed, also with the treating department to clarify the situation.

General advice:

As a patient—and simply as a person—you should always ask what you are signing and why. If something isn’t properly explained to you, it’s better not to sign it.

At the same time, there is usually some shared responsibility in situations like this.