You'll start to feel sick long before you have enough to harm you. Just make sure you're also replenishing your salts, not just drinking excessive amounts of water, or you'll throw your body's chemistry off.
When you drink too much water, you will just feel extremely bloated at the time but it passes quickly. You will be fine, but I think you should spread it out over time more and not consume that much at once unless you are thirsty.
Let your body be the one to tell you if you need to drink more, if not, don't consume as much at once.
here is a water consumption calculator - it calculates depending on ones weight .... just keep in mind that water requirements can change depending on physical activities, the weather, pregnancy and breastfeeding and even your health condition...