Sorry about the bad experience. i am with @Dennis, when in doubt and low disconnect - when in doubt and high use a syringe.
Most pumps have safety protocols that prevent unintended insulin delivery, but I happen to design automatic systems and I knwo first hand that anything that can fail will fail, and typically at the worst possible moment.
That being said I have never had a pump deliver when it wasn’t supposed to, however, I have had many lows.
about every 3-7 years, my body starts making insulin again. I have had T1 for 37 years and this is unpredictable and weird…but happens. I went 7 days without having to bolus - the way I found out was I bolused for a big meal and had a 5+hour low. each time I used the bolus I was low and occasionally overnight (when my basal program is higher,) I would go low. I put my cgm back on and watched that dumb thing “flatline” right through meals and all with zero bolus insulin. Made me happy and sad at the same time.
My brother is a doctor and we joked about being “cured”, and of course I know better. As predicted, eventually and without warning I had to start right back up again. oh well “working pancreas”, see you in another 3-7 years.
Also, once I knew what was happening I did enjoy a little pizza and ice cream during this time. I considered sending my data to Dr. Faustman, who predicted that islet beta cells can regenerate, but then are subsequently re-attacked by my immune system.
all I am saying beyond the story, (and all joking aside for a moment) is the proof is in the disconnect: if you disconnect and are still low, it’s time to consider all other possibilities.