Inner ear issue

Yes.

My understanding is that there are numerous things that can cause dizziness, from the merely irritating to lethal.

I know it sounds trite, but maybe see if a physician can get to the bottom of it. None has ever arrived at a satisfactory explanation for me, (and I've seen a small army of specialists) but vestibular rehabilitation therapy has been of some value. (It ain't a quick fix though. it takes near Jobian patience.) 

It may just be "motion sickness". If so, progressively desensitizing yourself to flip turns could help. As a youth, it took me several years to work up to doing flip turns throughout practice. As an adult, I've had episodes of vertigo. It often takes me months to work back into doing flip turns again afterwards. I had such an event shortly before the pandemic hit and chased us all out of the pool. If I ever return to swimming, I suspect it may take months to a year to get back to  doing flip turns again.

Yes.

My understanding is that there are numerous things that can cause dizziness, from the merely irritating to lethal.

I know it sounds trite, but maybe see if a physician can get to the bottom of it. None has ever arrived at a satisfactory explanation for me, (and I've seen a small army of specialists) but vestibular rehabilitation therapy has been of some value. (It ain't a quick fix though. it takes near Jobian patience.) 

It may just be "motion sickness". If so, progressively desensitizing yourself to flip turns could help. As a youth, it took me several years to work up to doing flip turns throughout practice. As an adult, I've had episodes of vertigo. It often takes me months to work back into doing flip turns again afterwards. I had such an event shortly before the pandemic hit and chased us all out of the pool. If I ever return to swimming, I suspect it may take months to a year to get back to  doing flip turns again.