First of all, you need to check whether you are developing low blood sugar during afternoon hours. You need to check your diabetic profile - blood sugar 6 times a day for atleast 2-3 days with the current anti-diabetic drugs that you are taking:
Morning: fasting
2 hours after breakfast
Before lunch
2 Hours following lunch
Before dinner
2 hours after dinner.
If sugar is falling, drug dosage needs adjustment. If not, write back to us giving some more details about the spinning sensations.