Hi Lou, I'm wondering if the cprrection you gave is the cause of your hypo? I was reading back through yesterday's tests and their timings and it's possible that the 15 was a peak. Yuo still had active insulin from your mealtime dose and this would still have been working to bring your levels down. I only correct if I'm still high 4 hours after injecting.
Do you often do corrections? I think that this can make things very difficult as you can never be quite sure how much active insulin you have still knocking around, plus the correction will extend the period of active insulin. So, last night what may have happened is that you were 15, but perhaps starting to come down. You corrected, this would have taken another 4-5 hours to 'clear' your system, so would still have been working long after you went to bed, causing the hypo.
I think you need to be brave and not panic if your levels go up to the mid-teens 2-4 hours after eating. Wait until at least 4 hours and see what you are then. The more you learn about carb counting, the more confident you will become that you have got the dose right, and it might just be an issue of timing the dose so the peak of the insulin matches the peak of the food.
I sometimes test after 2-3 hours and am quite high. The other day I tested at 10.8 at 3.5 hours, but by 4.5 hours I was 5.5, so dropped 5.3 in an hour with no extra insulin!
Hope I have explained this OK, I do seem to have rambled on a bit!🙂