Am I overreacting?

Today, I had an OB appointment at 2 in the afternoon. Unfortunately, my fiancé is stationed overseas so at each appointment, he just FaceTimes me to be a part of it as much as he can and I appreciate that very much. I always let him know way before the day/time of my appointments. However, today he had Duty (so they expected him to stay at work a little later). I didn't mind because work is work, but he texted me at 1:45 asking me what his number was, and I just replied with "For?" And it did not deliver. I called him because it was nearing the time of my appointment and no answer. I texted him again, and it was still not delivering. I got upset because he just asked me for his own number and then vanished and now he's about to miss our ultrasound? Anyways, I call the office to let them know I need to reschedule because I know that he wants to be a part of all of my appointments but for some reason, was not letting me know what was going on. He calls me at 2:40 asking me where I was, etc. I asked him the same question and also asked why he didn't answer my calls. He told me he sped home and that his phone was "acting up." I was just upset and disappointed because he could have told me he was leaving work instead of asking me for his number which when I asked why he did that, he told me he had to write it down in case they call him back in for Duty.