I agree, pretty much the color to expect. Sometimes a pullet's first few eggs can be "different". It is pretty complicated putting the egg together in her internal egg making factory, sometimes it takes a while for her to work out all of the kinks. One of the things that can be off is how much pigment she makes or she could have an issue with her shell gland on applying that pigment. Her eggs will always be blue or more likely green but the shade of green might change from that color some because of this.
That egg is basically blue throughout with brown pigment laid on top to make it look green. When you open that egg you can remove the membrane from inside and see that blue or you can rub or wash that brown off to show the blue. It is fairly common for the amount of brown pigment to drop over the laying cycle so that shade of green could lighten. I'm not talking about next week, I'm talking months.
Something else that can happen is that the egg will get bigger the longer she lays, especially in her first month or so. If the amount of pigment she makes remains the same then the egg can look lighter since that pigment is stretched thinner by the larger egg. This you might see over the next several weeks.
Lastly, it is possible for any hen or pullet to just have a glitch. Egg laying is a pretty complex process and occasionally one might have an oops. I think we are all entitled to an occasional oops as long as we don't make a habit of having the same one over and over again. Don't be shocked to see an egg that has a thin shell, no shell, double yolked, no yolk, a different shape or even a different color. These don't happen that often, sometimes never, but they can.
With all that said, unless she is having some type of startup problem that is pretty much the color you can expect but don't be surprised if it gets a little lighter over time. They usually don't get darker.
