Lillian gets the card key from the clerk (She doesn't seem to impressed with you at the moment, given your current situation. But either way she plays along and pays for the room, which is good since neither you nor Vera could afford it right now.) and hands it to Vera so you and her can get into the room.
After some time of studying what seems to ail you, you realize what it is, for you are intimately familiar with this type of effect. A curse has been set on your soul. Tomorrow by midnight your soul will be torn from your body and be dragged into the underworld. Your Phylactery may be able to prevent this from occurring, but you honestly aren't certain. If you are in your regenerative state, however, you know for a fact that it will not be able to stop the curse from tearing you from this world, so it is of the utmost importance that you stay in this form until tomorrow at midnight or you will surely be permanently eliminated.
As for how to get rid of the curse... That is a difficult process. You do not believe that any old item in a magic store would be able to help you. The priests might've been able to, but that seems unlikely at the moment... At that point, the easiest way would be to figure out who put the curse on you and eliminate them. Also account for an extra phase of figuring out how to counteract their effect once they are eliminated.
Curses of this strength are generally placed when the caster has direct access to someone's personal items or their essence.
(Do you have any questions regarding this?)