Sound sensitivity might be the worst only because it is the least managable. I can control my scent environment pretty well, wrap myself in the softest things and darken everything, but the sound of my own footsteps is a hammer on my already pounding headache. Even the faintest sounds coming through the walls and floors are only amplified by putting in earplugs. The sounds of myself even shifting as I lay waiting for medication or sleep to wear away the migraine can exaccerbate the head pain, vertigo and nausea.
Really though it's the combination of all the sensitivities. It's just painfully and nauseatingly overwhelming.
I might even say "prioperception" is the most troubling sense. My sense of self, size, orientation. I will suddenly feel tall, or that my arms are long and light. Even lying down, the world or myself seems to spin.
Yes. Now that I've thought it out. I'm going with prioproception as the most impacted sense as it is my sense of myself and I have yet to find a relief for this.