good players take it all in before making a conclusion. i would advise you don't look at one or two pieces. try and take in as much information as you can without prejudice. then make a decision.
What are good players thinking patterns before moving?

Check out these articles by Dan Heisman, he has quite a few on thought process and time management that are excellent.
http://danheisman.home.comcast.net/~danheisman/Articles/subject.htm#Analysis
Good luck.
This might be a silly question, but since I was a spectator in a chess game yesterday and saw some traps, I usually don´t see, when I play myself, I wondered, if my thinking patterns are wrong, cause I concentrate too much on my own moves, instead of spending more time to analyize my opponents moves.
How do good players think before a move? Example:
1. Why did he make this move?
2. What are the dangers?
3. What is my best move now?
4. What will my opponent respond?
5. How will I react on his respond?
As you might see, I´m quite a beginner. So I have two questions:
Is the above thinking pattern right or missing some points?
How much time should I spend on the single questions (specially in games with 15 minutes or less on the clock)?
Thanks for helping!