My dog bit a off leash dog?

I was taking my dog out to go to the bathroom and a lady comes walking around with 1 of her dogs in her hand and 1 dachasund running loose (no leash). The dachsund runs up to my dog barks and provokes my dog while still advancing towards us, my dog in responce bit her dog as it kept coming towards us. I recommended that she keeps her dog on a leash and immaturely, especcially since she's probably older than me, used some choice words and left. I live in Arlington Texas and there is a leash law here where the dog must be put on a leash when not fenced in. Someone help!!! What actions should I take being that I live in an apartment. And I want to ensure that I am not help liable for anything being that my dog was on her leash and the other individual didn't. What should I do............