Rock chip? Same thing happened on my 1 week old 4runner when I bought it. I didn't get it replaced until almost 2 years later though... Call your insuarance and see if they'll replace it at no cost to you...
Had a 2 foot crack on my windshield after 3 months. Had it fixed and insisted with my insurance to replace it with Toyota glass which they did. One week later a small rock chip. Another week later another rock chip. Next time I will try non-Toyata glass if it is better - although I will lose the hydrophillic (however it is spelled) stuff.