One thing to check when you’re low is your remaining “Active Insulin.” This is how much insulin you have left in your body from the last bolus. On my minimed pump (I see you have the Ping, so it might be similar) the way I check this is I pretend to give a bolus and when it gets to the screen where it breaks down carbs, blood sugar, correction, there is an “Active INS” section which tells me approximately how much insulin is still active since the last time I bolused. One thing that might be happening to you is that with a combination of high basals and overbolusing, you have too much Active Insulin in you, which would mean that not only are you low–at 30, 40, even 60 or 70–but that you still have insulin bringing you lower. So even with 3 or 4 twizzlers, if you still have that active insulin, you might only be putting enough sugar in your body to compensate for the remaining insulin, not enough to cover that AND bring you up from 30…which is quite low.
Additionally, this active insulin feature does not account for the active basal insulin you have in you, so if your basal rate is set too high, you not only have that hour’s basal active in you, but you likely have 2-3 hours of slightly excess basal insulin bringing you down. Outside of doing a basal test, what I would suggest for your next low is (1) checking how much active insulin you have left and then (2) putting in enough sugar to cover that PLUS enough to bring you up. The cereal is likely too many carbs (as your BG of 390 showed). I would try some juice next time. I would stick to fast acting sugar like juice or glucose tabs, just while you’re figuring out how to best treat these lows during the confusion of potentially too high basals and overbolusing.