Yup. You definitely missed something.
Of all the starting planets, Tython as the most xp. Even with a 25% deficiency, there's more than enough there to get you to 10.
As for medpacs and stims. Don't buy those either.
You get more than enough medpacs from quest rewards and loot. And stims aren't worth the money.
If you're really worried about it, take Biochem as your crafting skill. Which is pretty universally considered the optimum crafting skill for first character. (Since it's the only one that can really benefit all alts.) It's the easiest to level of all the skills, and you can keep it "up to level" fairly easily--any of the of gear crafting skills will ultimately start to fall behind unless you spend a lot of cash.
The Green medpacks and stims are way better than anything you'll find or buy and blue stuff isn't hard to make either and they add a HoT. Plus, the purps (also not too hard to get) are reusable (unlimited). Also, you can get packs that heal both you and your companion. You can't buy those from any vendor and they get expensive on the GTN.
Oh, and the Ancient Droid isn't an elite but a champion (gold and silver star) Elites just have plain gold stars and they're all over the place.