Hi, thanks for posting in HCM 
I have understood your concern 
1. your post prandial sugars are high so you needs increase in the morning dose as a tablet or basal 
insulin.
I can suggest you to take tab.januvia50mg once in the morning , recheck the sugars after one week and needs dose adjustment.
if not getting controlled with tablets , better to take low dose basal insulin.
2. reason for giddiness may be due to           
hypotension or           
vertigo.  or
            uncontrolled blood sugars or             
I can suggest you to get done 
ECG
ECHO 
BP check while having giddiness 
tab.
vertin 8 mg twice daily for 5 days
3. your weight is more and that is also contributing to uncontrolled sugars 
suggest you to reduce weight by regular exercise and diet control.
hope this helps you 
any further questions please let me know 
thanks