Well...
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Best run out and get a hydrometer then if you don't have one. I prefer a refractometer which is such a better device to use.
Is this is your first batch ever? Measuring the gravity is really important because fermentation is not linear over time. Develop a habit of checking...
Roughly, a stable reading means the bulk of the fermentation has occurred but it still may need time to taper off and condition.
Think 2-3 weeks in primary for average strength beers as sufficient and the rest of the conditioning can happen in the bottle. Once you've established that the reading is stable- which could be as soon as 7 days you can think of packaging.