Zayd, I don't speak from experience because I converted my license and, therefore, didn't have to do the test.
A friend of mine did and he failed the first time. I think you have to take lessons before you take the test but I stand to be corrected here. As far as I know, you should not drive until you can get your Qatari license. I know a lot of people do, but you always run the risk of the police not accepting your international license. In that case, if you get into an accident, the insurance might not pay for the damage.