Please Help!

I work in Texas, and I went into work at 4:30pm and was told that we had a mandatory meeting first thing tomorrow that i was not given a 24 hour notice on and it is also my day off. Due to it being my day off I had doctors and counciling appointments for my child due to a horrible incident that happened to her. WIth that said, my boss told me I can no longer work there if i could not attend the meeting, I tried to exlpain to her i already had prior arrangements, but she ignored me and began to chew me out for not being "a reliable employee". She then interrigated me and pried into my personal life that occurs during my off time, about what was going on that day that was so important that i could not make it to her meeting. I finally told her some information that had to do with my child and a sexual assult. only after then she backed off. Did she even have the right to know what i was doing on my days off during my personal time? Doesn't she have to give me a minimum of 24 hours notice to come in to work unexpectedly? I felt herassed, abused, and an invasion of my privacy about things that i didn't want people knowing.