I think we need a bit more information before we can help you
When you say your numbers go up & down like a roller coaster what’s the numbers? is there big rises & drops? Are you using. CGM or finger prick to test? If your using a finger prick how often are you testing
BG aren’t a static thing they fluctuate quite normally, sometimes within 5 minutes. What are you expecting to feel? Are you below 4 and not feeling the hypo? Or are you high and expecting to feel rough? Are you on any medication for your diabetes?
Sorry for all the questions but the more info the better
As has been said, BG levels change al the time. Carbohydrate/glucose in food is the biggest single influence but our livers are constantly adjusting levels in response to stimuli. I'm attaching a graph of a non-diabetic person's CGM to illustrate this: the "X"s are the points where the person ate. You might also want to take a look at the bit of research on what non-diabetic BGs look like.
Use of continuous glucose monitoring (CGM) is increasing for insulin-requiring patients with diabetes. Although data on glycemic profiles of healthy, nondiabetic individuals exist for older sensors, assessment of glycemic metrics with new-generation ...