How long have you been T1, Mariam? Did you know that if insulin doesn't absorb properly, it hangs round under your skin for any amount of time thereafter - but importantly - remains active for up to 12 years. So if one day a pocket you happen to have, suddenly decides it will absorb - we're stuffed for hour after hour after hour.
And there's no way of telling whether you've got any - or when they'll decide to break free, if they ever decide to. All in a day in a diabetic's life ........
I had one that there couldn't possibly be any other reason for but rather hilariously - whilst in with my DSN at the hospital! We were both late home that Friday - I couldn't drive obviously and she wouldn't leave me, so couldn't lock up and go home and do her husband's dinner. But he didn't mind when she told him why she was late - cos he was T1 anyway!