I feel like I'm in an elevator. The floor feels like it drops out from under me. I have been under a great feal of stress the past few days.?

Subjective dizziness. There is presently accumulating evidence that the neural pathways for anxiety and balance disorders overlap. Consulting a neuro-otologist is the most obvious thing to do. Again there is more and more evidence that stress can be associated with balance problems and that treatment for the anxiety can result in resolution of the balance problem. Chronic subjective dizziness is now well documented.
Cataplexy? These symptoms could be consistent with cataplexy. Feeling as if your legs are giving out - in particular with intense emotion -can occur with narcolepsy. Other potential causes would include: sleep deprivation, dissociative episodes, orthostasis - low blood pressure, neurologic conditions, hyperventilation/anxiety, or even vertigo. Any new meds/supplements/alcohol added or abruptly stopped?