Hi Coatl--
Everyone so far has given you
really good advice. Finding a gender therapist, a good endo, etc. are all very important.
One of the things to see if you can find is a support group. I didn't notice if anyone said in your other replies, but try googling the word 'transgender' and the name of your city, town, or nearest major metropolitan area. You should (hopefully) find out whether or not there's anything near you. Support groups are great. Knowing that you have brothers and sisters going through the same things is an amazing feeling.
Also, people in your area should be able to give you some advice on what therapists and endocrinologists are worth seeing. If the therapist you are seeing seems like they're not very supportive, look for a new one. You are an adult, and can make your own decisions on that score.
Took a quick look at your pic, I think you'll do fine. 18 1/2 is definitely
not too old, especially as some of us are transitioning much older. Hopefully your beard hasn't filled in all the way (I was probably in my mid-20s by the time mine did), so that will make laser/electro on your face a bit easier.
Re:hips. I've always had pretty biggish hips for a guy, but after six months on HRT, I'm realizing that it didn't help much. Now I have small hips for a girl.

You might be in the same boat. All in all though, it's really not big a thing to be concerned about. There are lots of cis-sexual girls with small hips.
One thing to remember about your looks: no one's perfect. Even supermodels in
Vogue are airbrushed.

If you ask the most beautiful woman you know whether she likes her body, I can guarantee she's got something she wishes were different. The good news is that you don't have to be perfect. It's enough to just be yourself. Don't worry about it too much. You're young enough that HRT will work some incredible magic on you.