Sorry, just a few thoughts and nothing 'in stone'
Adrenaline (and other hormones ) are released in panic situations or when more glucose is needed in a hurry by the body. (fight or flight).These hormones in turn stimulate glucagon which will cause a release of glucose from the liver to fuel the expected energy expenditure. This causes higher glucose levels .
This doesn't necessarily occur just when you're hypo. Personally, my highest glucose levels the last 6 years occurred after being scared stiff, driving in heavy snow on snow chains.
Normally adrenaline will cause insulin levels to fall but this is not possible when insulin is injected, so perhaps (not sure) if insulin levels do not fall in response then this could cause a further release of adrenaline/glucagon/gluose.
If these hormones are 'out of balance, I can see how a rollercoaster could arise.The symptoms you describe are those I read of too much adrenaline being released.
So, for the moment, I would listen to your nurse. Find out how she suggests you should lower your insulin and let her work with you.
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