Ripped off by Hotels.com - what can I do?

I booked a room for work travel. I couldn't locate the # of the hotel where I always stay, so I googled it. Thought I had the hotel chains 800#.I asked for the "state rate" , all my employer, will reimburse for. Booking agent ured I would get it - lowest rate. Got $148. I told her this was too high and I just wanted to book direct with hotel. Was told once they had my credit card# (my stupidity) it was booked and "tough luck" . I didn't say to book it - I didn't even have a conf#. Turns out 800# was HOTELS.COM. 1 1/2 hours and 6 phone calls later - all I can do is cancel my credit card and file a fraud complaint. I've has this card for 20 years and this will mess with my credit history. Who can I file a complaint with? Hotels.com just gets me call centers in El Salvador and Manila who put me on hold. Help! what can I do? (in addition to making sure of right 800# & NEVER giving mycc# )Thanks for your help!