Before I came to Doha, I had been driving for years. But as with any other country, the first couple of weeks driving in some new country gets some getting used to. There used to be many more round abouts btw :)

Like the others said, stick to your lane and be careful in a roundabout, as some drivers don't notice how they take an RA in a straight line so they end up crossing three lanes..lol
You'll be fine :)