You're losing at a reasonable pace. You feel good, you're not hungry, that's all excellent. Keep doing what you're doing!
If you were at risk of damaging your metabolism, you would feel rotten, exhausted, sleep more, living with near constant ravenous hunger with insane cravings for HEALTHY things, think wanting to pick up a rotisserie chicken and eat the thing whole, fantasizing about salads and hard boiled eggs, that sort of stuff.
In nearly 10 years of mentoring on a bodybuilding board I saw two categories of true metabolic damage. One: Hormonally related, this included post pregnancy and perimenopausal. Women are at an 8 times higher risk of thyroid disease because there is a very real link between estrogen and thyroid hormone. Hormonal surges can create issues and hormones are linked to diet. A sluggish thyroid can slow your metabolism by around 15%, enough to allow serious weight creep or make weight loss close to impossible. Also, my personal observation is that hypothyroid impacts your appetite. Your body is low on energy so it sends a signal the only way it can, stimulating appetite saying "SEND CALORIES!"
The second way I've seen metabolisms damaged is with SEVERE dieting in an already lean individual. Women who compete in bodybuilding competitions generally have something like 12% bodyfat (compare that with the average normal weight woman carrying around 25%). I've known a couple competitors who didn't want to give up that ripped look, despite repeated warnings to get off the restrictive diet and gain necessary fat. In one woman it created a horrible cascading hormone crash. But bear in mind,
that woman was attempting to maintain close to a 10% bodyfat.
Finally, read this:
http://www.nowloss.com/starvation-mode-myth.htm
Congratulations again on the success you've had with your journey and keep up the good work!