I will find myself increasing insulin dosage again and again to no avail because my glucose levels simply won't get into range. then I'll get it right and they'll be in range for a few weeks, before the insulin will need to drop rapidly due to hypos, but then of course after a period of time I'll be back raising it all again!
Yes! Same here!
One week I might need 4 units for the exact same breakfast which needs 12 units a week later, on days with similar activity levels.
I know many T1's do well on set insulin to carb ratio's for different times of the day, but in my case those ratio's fluctuate all the time.
It could be injection sites, age of insulin, hormones, exercise, hot/cold weather, sleep, stress, how far you are down in a vial, menstrual cycle, hydration levels, daily activities, carb counting food not having accurate labels, lipohypertrophy
Of all the things
@ert mentions, for me it can only be hormones/menstrual cycle or something like that, because the changes in the amount of insulin seem to follow a tide-like pattern: they'll flow to needing more and more over multiple days, stall, and then ebb back to needing less and less.
It's not like I need 4 units for that breakfast today and then 10 units tomorrow or such, which would be the case if it was age of insulin, weather, hydration, activity, carb counting or bad sites to inject.
I haven't found a very clear pattern corresponding with my cycle, except I usually (but not always) tend to go low right before menstruating. This could be due to being 44 and possibly early signs of the change though.
For you, at 16, the first thing I'd do is monitor your cycle along with your blood glucose/insulin need to see if there is a pattern.
The way I work with this ebbing and flowing is to pay close attention to how much insulin I used yesterday and the day before, and how those doses affected my numbers, and choose todays doses keeping in mind if I needed a lot, a little or somewhere in between. Together with carb counting and factoring in things like exercise and stuff.
Another possibility may be the honeymoon period, where your pancreas is still producing some insulin but not in a predictable way. How long have you been diagnosed?
I'm in almost 5 years, and a C-peptide after two years showed I still produced some insulin at that point, no idea if I still do.