Why does my bank account say i have negative balance when i didn't overspend?

• business bank charges
• refund bank charges

Yesterday I had $.84 left on my bank account. I spent $.62 and that should've left me with $.22. Payday was supposed to be today so I called my account and it said I have $-.87. $1.05 has been taken from my account for some reason.

Additional Details

Never mind. I called at the exact moment I was getting paid. I dont know why I had a negative balance but its good now. I just wonder if they still took it from my account.

Why does my bank account say i have negative balance when i didn't overspend?