I usually have bad dreams regardless if I was happy or sad the whole day. I really feel scared and I often think that it came true or that it's REALLY going to come true one of these days.

I found out that talking about those dreams help shoo it away. And it's a lot more nicer when the person you're talking to tries to console you and says, "don't worry, it's just a bad dream" because it reinforces the fact that it IS just a dream, and it's just images in the subconsious (it's not real or that it's a "sign" of things to come).

Talk it over with someone who you know will not snort about it or laugh in your face for being scared. Find someone you know who is caring or who is willing to listen.