So i think beginner luck is due to playing gambling in fear of not to lose the investment and that too playing without any strategy is giving profit but as soon as you start to use strategy and play and loosing starts it.
I'm not sure I can grasp how your fear of losing money can impact the probability of winning, but I agree that with a strategy you can lose much more than when playing without any. I think emphasizing the fact that beginners usually play without any strategy you are, probably, making a good point. Maybe that's how we can explain the so-called "beginner's luck", or at least partially explain it. Newbies play without any strategy and that's why they win more frequently than veteran players whose strategies kill their luck on a regular basis.
I disagree. Your fear has nothing to do with your chance of winning. I even think that fear is a good feeling to have while gambling. Although it can't affect the outcome of the game in any way, it can help you to stop at the right time either saving you from losing everything while chasing your losses or making you quit while having good profits. Also, the "techniques used by veteran players" are usually of little help, don't waste your time studying them.