You could have probably also thrown the question back at her and see if she's carrying one. Lots of girls do.

But Bill's suggestion is right on! Then again, some girls you really can't spell.

Well at least next time she texts and makes sexual hints, you can reply back that you're scared of sleeping with her because she seemed to prefer men who aren't responsible. And you really don't want HIV. This is, assumming, you can easily move on to other girls.