Ratings are very subjective, and it really depends on your experience... if you've been playing regularly for a year, 600 isn't very good... on the other hand, if you've only been playing chess occasionally for a couple months I'd say it's pretty normal. As for winning/losing streaks, it's also very dependent on your mental state. Sometimes, when I'm wide awake and "in the zone", I've been able to get completely winning positions over GMs over the board. When I'm drunk/tired, I'll completely forget my queen is hanging.
Just remember, no matter how good you are, there are almost certainly tons of players who are much better and tons of players much worse than you.
whats a 600