I was doing a difficult emergency drain cleaning job in a hairdressers and splashed drain water. Am I liable?

I am being sued for a large sum. I feel this is unfair because I was doing the client a favor, the drain had collapsed and was full of rubble,I worked extremely hard so the woman would not have to close her business and dig up the floor. The job was a success and she clearly saved a great deal of money. I didn't even charge her the extra hours because I had made a mess. The claim is 100 times the real damage. I feel so offended!