Sore loser??

When does one be called a sore loser? Does showing anger at the pre-match arrangements after the match also a sign of it? One doesn't consider much about it if there is a confidence of winning even after being aware of the arrangements. But when it results in unfavorable result, one tends to blame the situation. Writing always takes the anger out of you. Now, it seems like it went the right way. Maybe the reason for it to happen is still not fine with me. Been following for a while now. 22 years is quite a while, I should say. First weapon was withdrawal, which did more harm than good. No good at all, rather. Second was the 'you cant beat them, join them'. Not sure if i follwed that. In a bad mood, feeling so.