You did good, the main thing is to remain professional to your clients at all times. Remember you're the professional, not them. Also whether she sent you the text or not only God knows, because sometimes these things does happen when a text doesn't go through. One way to avoid that in the future is to make it a rule that when it comes to important things or messages don't text or rely on texts, you need to atleast call directly to talk to the clients and confirm your appointments or cancelations. I never handle important issues just over texting, I like to meet the individuals in person mostly, so that I can read their body languages and feel their emotions and the same goes for them. At the very least if meeting in person isn't possible due to unforseen circumstances, I try to atleast talk to them over the phone. Of-course this may not necessarily be the best way of handling things, but it works for me, you can model it or come up with your own how ever fit you best. These kind of incidents should be a motivation for you to accomplish your goals even more and feed on the energy to take actions toward them. Good luck my friend, hope all work out for you soon.