Hi and welcome from me too.
Don't worry, it is perfectly normal to be overwhelmed and scared at the beginning and unfortunately levels can be most erratic at this time because of the honeymoon period although for some people their own insulin production smooths off the edges, others of us found it unpredictable and unhelpful to say the least, scary sometimes. Gradually you will start to see patterns though. They won't be exactly the same but you might start seeing that you drop a bit low (or very low) 3 afternoons out of 5 or perhaps your levels shoot into orbit after breakfast most mornings. You have to look longer term than just day to day to see these patterns although the "Daily Patterns" feature on Libre can sometimes help to identify them once you have enough data built up.
Talking of Libre, it might be pertinent to point out that Libre and other CGM systems have limitations and knowing and understanding those limitations is important, particularly when dealing with hypos, which is something you mention. Once Libre indicates you are below 4, use your finger prick BG meter to assess if you are actually below 4 (Libre exaggerates sometimes. My sensors generally read about 1mmol below finger prick readings, so Libre might say 3.6 when I am 4.6. This may well be the case for you too and could be why you didn't feel hypo when Libre was showing 3.6. Added to that, Libre reads interstitial fluid(IF), not blood and IF is about 15mins behind blood, so if your BG levels are rising, the interstitial fluid will be 10-15 mins behind. Libre has an inbuilt algorithm to overcome this time lag, which extrapolates the previous readings to predict what the current reading will be. This is fine when your levels are level or going up or down slightly but not when they are changing direction for instance when you have dropped into a hypo and then had some fast acting carbs to bring you up. Libre will almost always show your levels continuing to drop 15 mins after taking your hypo treatment, due to this algorithm whereas a finger prick will show you the true situation, so always be guided by your BG meter when treating a hypo. If you just go by Libre you will almost certainly over treat it and end up too high and then you are on the BG rollercoaster and it is usually a bumpy ride.
There are a few other limitations all which are documented in this thread....
Moderator Note: This helpful reply was copied from another thread as it details some of the commonly experienced limitations of continuous glucose sensors. My blood sugar has been in perfect range for days now, but although I haven't changed anything, I'm starting to get very short periods of...
forum.diabetes.org.uk
Just really want to say that it does gradually get easier. You are on the very steepest part of the learning curve at the moment but gradually things will start to make a bit of sense and become more routine until you are sitting eating your meal and trying to remember if you actually injected for it. I can wake up in the middle of the night hypo and eat a couple of JBs and be back to sleep in minutes, or wake up high, calculate a correction dose, inject and be back to sleep without even putting the light on! It gradually just becomes second nature. The only thing that doesn't seem to normalize is your frustration when diabetes doesn't play by the rules and moves the goal posts when you aren't looking and the strategies and ratios that worked well for the last 3 or 4 years suddenly don't work any more and you have to develop new strategies. Libre and other CGM are wonderful though and take a lot of the guess work out of it. We are so lucky to be diagnosed at a time when we have this great technology. My uncle didn't even have a BG meter, had numerous really serious hypos where he was found semiconscious and hospitalized several times with DKA and yet he was still cycling solo at 80yrs old, so despite it being pretty scary the odds are stacked well in our favour these days, with the modern insulins and CGM and insulin pumps and closed loop systems to come for most of us in the future, making our lives with diabetes much easier to manage.
