I found this article on MS and the sense of smell and I find that I have the exact opposite effect as what is described here. I smell things sooner than others. I react as if certain smells, especially harsh cleaning agents, are poison and my respiratory tract takes a path akin to asthma. I can smell your anti-perspirant deodorant, laundry detergent on your clothing. Others consider these normal smells, but I need to move away if you've used too much of it, otherwise I can't breathe.

https://multiplesclerosisnewstoday.com/2018/03/19/ms-patients-poorer-sense-of-smell-even-at-early-disease-stages-study/

https://multiplesclerosisnewstoday.com/2018/03/19/ms-patients-poorer-sense-of-smell-even-at-early-disease-stages-study/

Then there is this forum on a condition called Hyperosmia which seems to explain some of it. In my case I don't believe it is a psychological root; I think it's the MS. I do note that it is less severe if I keep my mouth closed, but I also know that the bulk of smell is through the roof of the mouth. Even though I know these things, I still don't think it's a kind of hypochondria.

https://www.medhelp.org/posts/Neurology/Heightened-sense-of-smell/show/1122589

Too bad, because I don't take any recommended 'treatments' Neurologists don't study me. Good thing that I study me.