Do not give these people your credit card number!

I got online to make a reservation at Holiday Inn Express, Burbank, CA. I thought I was dealing with the Holiday Inn Express website. It showed a nightly rate of $215. It was fairly expensive because of a special event nearby, but still less than Booking.com. At the end, prior to my completing the transaction, it said "We have one more step before we complete this "pre-paid reservation". I immediately backed out of the transaction, realizing that I was not dealing with Holiday Inn Express. The next thing I got was a confirmation, showing that they had added $249 onto my reservation. What should have been $430 plus tax was now $679!
I immediately called their customer support number. The agent said that the reservation was non-refundable, but offered me a 10% discount. I told her that this was wrong because I had not completed the transaction. I wanted it canceled and refunded. She upped her offer to 20%. After telling her I wasn't interested in her offer and to transfer me to a supervisor. The supervisor said that she is "not authorized to refund my money". She was polite but obviously gets paid for saying "no."

The supervisor said that I could cancel with no refund or take the 20% discount. I told her to go ahead and apply the discount, but I wasn't finished with this yet.

I can't believe I fell for this. I feel really stupid, and I consider myself pretty worldly. I'm hoping this will be resolved through my credit card company. It's obvious that Getaroom.com's customer service is not going to make any effort to resolve this. Their 20% discount does not make me feel better. I only took it in case I really can't get a resolution from this.