It is a fair question, and a common one. A friend wears a guard, an article mentioned grinding, and your jaw has been sore on waking for weeks, so a guard seems like the obvious answer. Before anything is made, though, it helps to understand what your mornings actually involve: where it aches, how long it lasts, and whether eating is affected.
Guards are mainly used to protect teeth, and grinding in sleep is only one possible reason for a morning ache. Tired muscles, an irritated joint, a cracked or decayed tooth, wider health factors, and sleep problems can each be involved. A tooth that stings when you bite, a jaw that has started to open less, or snoring with breathing pauses would point somewhere a guard cannot reach.
So the appointment starts with talking and examining, and the appliance question comes afterwards. If you already own one, from a pharmacy or a previous dentist, bring it. Whether or not a guard is recommended, you will hear the reasoning and how we plan to check that the approach is working.