I have had this happen when a previous person was using it and it did not release after they left. A reload UI should fix it, if not, a log out and log in will sort this out. Since you are not in a cave or dungeon, you will log back right where you are.
Enjoy the game, life is what you really want to be worried about.
PakKat "Everything was going well, until I died"
Gary Gravestink "I am glad you died, I needed the help"
If/when it happens again, be sure to send an in-game /bug report so that the devs will have a record of this happening and plan to do something about it. After all, /reloadui is a workaround, not a fix.