I accidentally deleted the internal Macintosh HD in utility panel
So I'd like to preface first that I feel like such an idiot.. I went into utility panel to erase and reformat a thumb drive and when I went to click erase, I didn't double check that I clicked the thumb drive and since it was automatically on the Macintosh HD it erased, however, right below it there is an internal drive named Macintosh HD - Data and it's 141.86gb/500gb so I'm a little confused.
Furthermore, I am currently using the computer still as if nothing has changed. All programs, files and data still retrievable.
if anyone knows how to help me further I'd greatly appreciate it! (I'm on a MacBook Pro 2015)