Well, yes, eye color will change when you are angry. And in common, when you are angry, it is possible for your eyes to have some eye color such as red, for angry will just make your eyes have high blood pressure. According to some experts, the color of your eyes can change with the emotion and weather. And generally speaking, if your emotion is low, it can turn to light grey and light blue. And on the other hand, when you feel angry, or others, it will just make you have some eye bright colors, such as red. Besides, the weather can be another factor too. For many people, when it is really sunny outside and the sunlight hits your eyes, the eye color will become brighter. By the way, even some drug which will have side effect that it can change the color of your eyes. So just pay more attention to it.
Yes, they do tend to change color when angry or due to mood. My eyes, in particular, are quite interesting. They turn a bright hazel with a little explosion of spikes surrounding the pupil of the eye. When I'm in a low mood, they resemble some seriously dark chocolate, and when normal, they resemble dark brown, boring eyes. They're very cool. Blue eyes tend to go green when pissed off and turn to a lighter and grayer color when in a low mood. Same with green. Gray eyes can turn a multitude of different colors but tend to turn ice blue when pissed and a silvery color when in a low mood.
Well, I think you must have been quite nervous, and generally speaking, our eyes would not change their color under no circumstances, because the color of eyes is decided before we were even born, and actually our gene type and some anthropological reasons decide. But your eyes would be dilated due to some biological reactions.