Take a deep breath, sweetie. Feel better?
Ok, now nobody likes to be stood up. And it's not cool when it happens, either on purpose, or by accident. But we all have to recognize that occasionally there will be things in our lives, or our partners lives that may change plans suddenly. Sometimes phones don't work, or cars break down, or bosses demand that we work late. Such are the things of life.
Unless this is an ongoing problem (ie. you're being stood up everytime you turn around), then I don't think there's any reason to worry. It sounds like your boyfriend tried to get ahold of you, but for some reason, it just didn't work. And it sounds like he's sorry. Sometimes circumstances are out of our control, and things happen. Don't panic. Understanding and forgiveness are some of the most key parts of any relationship.
"Not everything in this magical world is quite what it seems"
"Remember, I'm pullin' for ya. We're all in this together!"