Fingerpricks are more accurate than sensors, so a sensor is no guarantee to prevent a hypo.
When I started on insulin I used fingerpricks and tested a lot to get an idea of what was happening.
Like you, I was apprehensive of hypos until I experienced one.
For me, I felt funny, a bit shakey, tingly mouth, and wondered if this was a hypo. So I tested and it was a hypo indeed. I ate two sweets and retested after 15 minutes, turned out I was well above 4 again, and that was the end of my fear of hypos (although I've had some nastier ones in the years following).
Libre gives out a two week free trial if you've never used one before, which can be very helpful in spotting trends and patterns.
If it were me, I'd save that trial until a little later. Finding the right dose of insulin can take some time, so during the first two weeks it'll likely mainly tell you your BG is on the higher side.
Once titrated up and seeing reasonable numbers, it can be of much more use to find patterns and see where you can use some adjustments in your meals or medication.
However, if using one now helps with the anxiety of starting insulin, it 's not a bad idea to use it now, and maybe buy one in a while.
Good luck and let us know how it goes!
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