Yes I do have a hydrometer. Honestly though I don't have a great understanding of how it works yet.
So here's a basic summary: You are measuring the density in comparison to water. The hydrometer will sink more in less dense fluids. So you take a sample, you read it, now you know the density of the wort/beer.
The density changes during fermentation because alcohol is less dense than water -- so it will get less dense over time. If the hydrometer reading is not changing from day to day, then you know that the "attenuative" phase of fermentation is done, i.e. the phase where the sugar is converted to alcohol. The beer may likely still benefit from some time in the "conditioning" phase of fermentation.
You can also get a ballpark ABV estimate by measuring the difference between the original gravity (OG) and final gravity (FG). The idea is that since the majority of the density change is due to sugar changing into alcohol, you should be able to calculate how much alcohol there is based on that change (there are other things that happen that affect the density, so ABV estimates based on gravity readings are just that: estimates). I forget the formula; just google for it and it's easiest to plug it into an online calculator or brewing software.
I'm planning to move the batch into secondary fermentation on Saturday.
You may want to read around on this site a bit first.
For starters, you shouldn't rack to secondary until you are sure the attenuative phase is done, i.e. the hydrometer reading isn't changing. That will probably be the case by Saturday, but you should make sure. Otherwise you can wind up with what's called a "stuck fermentation" and the beer could taste overly sweet and have a low alcohol content.
There is also a growing school of thought that secondaries are not particularly necessary. There's a lot of controversy over this, though, so you need to read what people say and make your own decision.
I think a lot of people agree, though, that most beers benefit from about 2 weeks in the primary. Whether you bottle at that point, or rack it to a secondary, or just let it sit in the primary for longer, that's a matter of personal preference. But IMO it will be better if you wait at least 14 days before taking action.
There are some who would disagree with me, though, so make your own decision. Just know that it's not as cut-and-dried as a lot of kit instructions make it out to be, and that furthermore a LOT of people will tell you that racking it after so few days is probably a mistake.
Yes, it is perfectly normal. 
