Expect to lose a lot of fights. A LOT. You will do yourself the greatest of services to not give up merely because you aren't winning. Everything that tools you will seem a lot stronger and better than the choice you've made, but the cruel truth usually is that the other player is that much better than you, not that their particular race, class, weapon spec choices are inherently stronger.

The lessons you can gain by sticking it out a while even if things seem bleak are invaluable. My first "successful" character had a record of 22 wins and 79 losses. That wasn't to say I had never had a character before that with a better win/loss ratio, but it was the first time I really felt I started to learn things and improve as I went along, instead of just giving up when things weren't working.