I am not seeing any jewelry in the photos, and jewelry can make a big difference. You are only 18, so no one expects you to wear real gold and diamonds.
I cannot tell if your ears are pierced, but if they are not, try to find a place/way to get them done.
Then try to find some of the kind of inexpensive jewelry that the younger girls wear --- a few bangles or bracelets, a long necklace, and some earrings of some kind, cubic zirconia, cut glass, or some simple hoops.
