Well, even if they happen rapidly and use the same server seed, client seed, and nonce, there is a salt that is added to ensure randomness. So,they should be just fine, it's that you don't always get a proper curve on low numbers, outliers are more likely, e.g. you can flip a coin twice and get heads both times, and if that's the length of your sample, it looks skewed, you only see it when you do it a lot.