Hello, 
Since you experienced sudden slurred speech with 
blurred vision, numbness left side with 
disorientation it looks like you suffered from sudden neurological problem like Stroke, 
brain injury, brain tumor.
These medical conditions can be triggered by 
hypoglycemia, low blood pressure, dehydration, etc.
You are suggested to visit a GP though you do not have any symptoms at present. You need to get clinically examined, get blood tests done to detect DM, BP, Cholesterol levels.
You will have to get CT, MRI, Carotid 
Ultrasonography, MRA, etc done. Your treatment will depend upon the pathology detected, you may be treated with medications or surgery.
Hope I have answered your query. Let me know if I can assist you further.
Take care
Regards,
Dr Nupur K, General & Family Physician