I am ignorant enough not to be able to smell the difference. I suggest you give more detail as I take this as a complete rule out and suspect others here will feel the same.
Cool, I'm a casual drug user. For me a junkie is someone that:
- shows erratic behaviour, she did, probably because of the damage taken by sustained usage
- does too much in a session, her eyes moved fast, her movements where really instant. Clear sign of someone on too much coke
- no sense of intimacy, she clearly got fucked in a strangers house and didn't cared for it, nor did she asked if it was ok for her to even start in the same place