Sounds like you have diabetes now. this needs to be assessed and properly treated by your Drs.
Aleve should not cause this.
the rehab is correct not to allow you to exercise / do rehab with such high sugars, which are dangerous. Normal non-diabetic level of blood sugars are 80 - 120 range.
You will need to reduce your carbs and take meds for this.
Please see your Dr. asap about this result.
If you ate foods high in carbohydrates, drank sugary liquids or juice before your session your blood sugars would be elevated. Don't feel Aleve raised your levels. Hope you are testing your blood sugars on a regular and scheduled basis, 326 mg/dl is dangerous. Good Luck -