I had half a tabk of regular gas and filled up the rest with special is that bad?

Its the first time I have done this. I drive a 2004 honda accord i'm worried I might of damaged my car by doing this

The car normally takes "regular"? You didn't hurt anything.

The "regular" (89 Octane) and the "special" (probably 91 Octane) mixed to form 90 Octane.

Buying "special" was a needless expense, but it won't damage anything in your car.

NO issue at all! Gasoline is fully mixable to start with only diesel is a no no. The car has this brain (computer) that outthinks all of us. It reads via sensors the quality of the fuel and adjusts for it. Glad to help ease your mind

The only thing you will damage is your bank balance for spending more on fuel your car will not benefit from.

The only damage you caused was to your wallet, it didn't harm your car. Unless your car requires "special" higher octane fuel you get no benefit from it.

No. Now that you know this you can find something really profound to worry about but this isn't one of them.

You won't have damaged your car.

No, it was just a waste of a little money.

What is "bad" is your grammar. What is "tabk?" and do you not know that "Is that bad?" is a separate sentence or is that you do not care for proper writing? Also distressing is that your are not able to read correctly the labels on the fuel pump. Also distressing is that you did not noticed the higher cost per gallon. To add "frosting" to the mistakes, the name of the brand, Honda, and the name of the model, Accord, are not properly capitalized. Then, of course, in true fashion to teenhood and Slanglish you failed to place aple dot, a period, a punctuation mark at the end of the last sentence. The last comment is that in spite of you being 16 years old with parents at home you prefer to text invisible strangers online compared to speaking with your parents or adult family members. Sad, tragic and upsetting to say the least.