I have now done this three times in 28 years with Type 1 diabetes.
My house is, let's just say a little, no, a lot crazy in the morning; five kids running around, lunches, breakfast and three diabetics to test, bolus, calculate, and inject. Not using this as an excuse, but it describes the setting for you.
So I am asking my daughter on the pump what her sugar is, and she is yakking to her sister about princesses or something and I am simultaneously dialing up my Levemir(so I thought) to 16 units, and I gave it. I then removed the needle tip to discard, and my heart sank, oh crap....I knew immediately that I just injected myself with 16 units of rapid acting not my Levemir. It is the same kind of the feeling you get if you have ever shut the car door and thought crap my car keys are in there.
Of course I had already taken my rapid acting dose of 4 units, so I now had to chase 20 units of rapid with an enormous quantity of carb. Lovely (Sense the sarcasm) Normally I would eat 5-10 gms Carb in the am.
What to do?
First time I did this was like over 20 years ago and I went to the ER and they screened me for being suicidal for which I was not. Back then they jammed the intravenous in my vein and filled up the tank with a dextrose drip.
The 2nd time I just drank a gallon of regular pop, not good, can we say nausea.
The third time they say is a charm, but not in my case. I had to head to work, drop kids off, basically remain some what functional for the remainder of the day. I am definitely going back on my pump!
I decided to fill up a 1 litre mixer bottle(the ones you make protein shakes with) with milk and 10 tbsp of liquid chocolate milk, you know the yummy stuff (in the right quantity)
I guzzled that down, took 10 units of Levemir (triple checked this time) so I wouldn't rebound later in the day. Off to work I went. One hour later I was sitting at 11 mmol, or 198 in the US. but still waiting for the peak.
Lesson learned.....Always triple check your insulin vial, especially with a house full of kids!