Hi Nooch1.
As everyone's sensitivity to Insulin is different. I dont think anyone of us would be able to advise on what a correct correction dose for you would be. At least not without obtaining further information and/or a history of your levels before and after food/insulin.
After experimenting with my sensitivity to Insulin and recording my levels for at least a week I know that 1 unit of NovaRapid reduces my glucose level by 3.0 mmol/L.
Others may or may not correct me but I do not think that a set dose of bolus insulin with meals is the correct way to dose. For example if you have a meal which has 45g carbs total and we say each 15g of carbs requires 1u insulin then 3u with that meal would be the correct dose. However if your meal equates to a total of 75g carbs then 3u would not be enough but 5u would be.
I know that does not help with working out how many units you would need for a correction dose but if you can carb count and match insulin dose with the meal then you would probably not have a need for a correction dose.
But as I previously said... after at least 1 week of recording all my carbs, glucose levels and insulin doses it provided me with enough information to work out that for me, generally... 1u of bolus insulin (novarapid) reduces my glucose level by about 3.0mmol/L.
I'm sorry if I have confused you. I'm not very good at explaining things by typing alone.
I'm sure there will be others who can explain much better than I can.
Best wishes.