Many people care about their rank. Me too, although I can hate myself for it. It becomes much easier to climb up the ranking if you admit you care. It also becomes easier if you observe some basic laws of gamesmanship, before blaming another loss on your go skills:
[1] "He who blunders last, loses the game." It's nothing to be proud of perhaps, but recently I played a tournament game in which I was dominated the whole game. I kept playing and was able to keep the difference under 10 points, but this was also because he managed his advantage solidly. Then he blundered in byo-yomi and made another mistake due to the consequent dismay. He was clearly the stronger player, but I won.
[2] Don't play super-blitz and if you do, manage time rather than moves. At the other end of the extreme, I recall a handicap game without time constraints where the fellow kept playing in a lost position and thought for ages before moving. I lost patience, concentration, and a big group in atari.
[3] See also /the philosophy of mistakes.
[4] There is probably nothing I hate more than playing a move, watching my opponent run out of time, then getting a game result that it was me who lost on time.