Sporadic migraine minor speech+cognitive impairment minor hallucinations like confusion of surroundings, mild paranoia mood swings occasional lethargy?

Complex migraine. Migraine auras not only can cause visual issues but also numbness, tingling, and difficulty with speech. The cognitive issues can be entitled "dysphrenia hemicrania transitoria". All may be best treated by a preventative agent.
Could be serious. Have you seen a dr? You should. Probably right away. I would if i were you. Many of your symptoms are likely best evaluated by a neurologist. It is not possible to accurately diagnose every condition or disease here on healthtap. Sometimes, people will ask around with family and friends about a real medical problem, while the process of asking around delays potential, life saving treatments.