Thanks for using the forum. I am happy to address your questions, and my answer will be based on the information you provided here. Please make sure you recognize that this forum is for educational purposes only, and it does not substitute for a formal office visit with your doctor.
Without the ability to review your medical history and examine you personally, I can not tell you what your pupil size difference nor your episodes of confusion/dizzy spells are caused by. However, I will provide you more information about these symptoms that you are having.
Pupillary asymmetry is not uncommon. In fact, 20% of the population have a slight difference in their pupil size. A difference of less than 1 mm is rarely ever significant. Differences in pupillary size are most significant when they are associated with other specific neurologic symptoms. The pathway that controls pupillary size does pass through the upper cervical spine, and problems in that area may cause pupillary abnormalities. A pupil that is large and does not constrict when light is shown on it is particularly worrisome and should be evaluated.
Episodes of dizziness that last seconds to minutes could be caused by an inner ear problem. Common inner ear conditions leading to dizziness include "Benign paroxysmal positional vertigo" or, BPPV, which occurs when one of the tiny stones in the ear is dislodged. Treatment usually includes repositioning of the dislodged stone through specific maneuvers. Another inner ear condition that causes dizziness but is usually associated with ringing in the ear and hearing loss is called Menniere's disease.
If dizziness occurs with other symptoms such as tongue heaviness/slurring of speech, difficulty walking, weakness on one side of the body or the other, or other neurologic symptoms, it may be caused by what is called a transient ischemic attack, or TIA, what is often referred to as a mini-stroke.
Sensations of mild confusion associated with a shaky sensation inside may occur with panic attacks.
You may benefit from evaluation by a neurologist and an eye doctor (opthalmologist).
Thank you for this opportunity to answer your questions, I hope you find the information I have provided useful, good luck.