My advise would be to get yourself on the DAFNE course if its available as it takes you back to as if you know nothing about diabetes. Will help you work out ratio etc. and would probably reduce the amount of insulin you take 120 before a meal sound really high. For example a typical ratio for a typoe 1 would be 1 unit for every 10g of carbs you eat. So going by this you would be eating 1200g of carbs which is alot. Also with correction doses it is said in DAFNE that you should not take any more than 4 units as anything above this does not tend to do anything for your bg. Again go and see your DNS would be the best idea and try and get on DAFNE.