It could have been worse. I did that on a credit card (paid them xxx.22 instead of xxx.27) and they gouged me for interest since I did not pay off the balance! The interest was about $9!
Ouch! As it was my fault, I paid it. But now I round up on credit cards. that extra 50 cents is not going to earn me any interest, and sure is going to save me from getting hit with an interest charge!