It looks like you're just missing captures in your games. Lets look at one:
Looking for threats, captures and checks is a key to seeing tactics and getting better at them. If you do this in your games and during puzzles you will improve. There are also some problems in the opening. You generally want to develop all your pieces so that they can participate in the game. Here are some tips on how to play in the opening of the game:
http://exeterchessclub.org.uk/content/ten-rules-opening
Rules have exceptions but following these should keep you safe in the opening most of the time. As you improve you'll start to learn about when it's ok to break such rules. Here's a good lecture by GM Yasser Seirawan on the opening:
no dont quit . chess is fun. I get so angry when i lose some stupid game i wanna smash the screen but i still play unless im grounded for swearing at my opponent after losing haha