Well, to me in general men don't like talking too much about "mushy" or "emotional" things. That's just a rule of thumb. They're not as in tune to their feelings as women are, so a woman talking about very deep emotional things may make him scared.
It really depends on:
-how long you've known the guy
-what your relationship is with him
-if you're dating (how long have you two been dating?)
-and what you were talking to him about
If you REALLY like this dude, then I wouldn't just write him off so quickly. To me that's kind of unfair. If you two are just dating, maybe for about 3 months or less, then him freaking out is kind of understandable.
Just relax, don't take it personally, and give him his space! He may be sorting out his feelings for you, or your deep emotional session may have caused him to get a little scared. No biggie. Just let him have his space. Let him call you, and the next time he calls, just keep the conversation light, breezy, and fun.
I think with SOME men you sometimes have to ease the conversations into deeper territory. YOu can't just throw some men into deep water and expect him to swim. Just gradually introduce him to deeper topics, but make sure they aren't TOO deep TOO soon. Keep it light if you're just dating this guy.
But if you don't really like this guy, or if you two have been dating exclusively for a while, then by all means...find yourself another guy who isn't so afraid of more emotional attachment!