I for sure have lost my mind

The battery life indication is just that - an [i]indication[/i] based on current/average use. Instagram - among many other media-heavy apps - is notorious for heavy battery use.

When you were using Instagram, the phone thought - based on current use (i.e. heavy because it was acting up and sucking up resources trying to do calculations) - that it would lower down to 27% if it continued at that rate for the near future.
However, when you stopped using Instagram (turned phone off), the memory was freed, the calculations and allocations didn't have to happen anymore and the phone then thought: ok, based on the current light use situation, it looks like it's actually at 42%.

This indication comes from the same principle when introducing the concept of [i]average[/i] in Statistics 101: "A man drowned in a pool with an [i]average[/i] depth of 1 foot" (the point being it's not the [i]weighted average[/i]). The average of 2 2 5 8 1 9 1 is 4, but what if the 1 in the weighted average has a weight of 8? Then the average is 6.6, making it a heavier estimate. Refer to the situation above.

I hope this makes some sense.

Machines are prone to error and miscalculations.

No, it's the phone. I once charged mine to 100% then shook it or something, it showed 0%...i was so pissed, then turned off and on and it was back

I'd say it's an i-phone or it's pretending to be one..

Is that all you got to worry about? 🤷‍♀️

IT must be an I-phone

If you have a galaxy their battery allows itself to charge in sleep mode or when the screen goes black.

iPhones have lightning charge, for a faster charge you can turn your charger to its other side and watch the charge at a faster speed.

Plus IG runs a lot of background processes in your phones, when you closed it, you can burn your battery out over using certain apps like IG, SC and other various ‘live webcam’ apps

Maybe you’re just overtired .. take care

Is it bad