I regret getting my hair dyed

I never had anything done to my hair before and wanted a cool change so i made an appointment at a salon. The website said it started at 250 and went up to 300 or 350 depending on hair length.

Then I went in and the said I couldn’t do the design I wanted and they also needed to cut my hair and give me bangs and I should chemically straighten my hair and also wear makeup everyday because the color I wanted would wash me out.

I wish I just left! They quoted me 600 instead of the price on the website and I wish I just left. I don’t know why I didn’t. It was the combination of already being there and having sat down for like 10 minutes already and idk. I need to be better at being more assertive.

And now I have dyed hair and I hate it. And it’s also shorter by 2-3 inches. I don’t want to go back to a salon to fix it, who knows how much that will be. I don’t want to spend any more money. Can I box dye my hair back to black? Should I just wait for it to grow out? How many years will that take?

I’m crying on the inside.