Does the teacher know I cheated?

So we were all taking the test and then the teacher left the class. So my friend asked me (not so quietly) for an answer and I tried to give her a hint but I ended up giving away most of the answer (again, not too quietly). You know, when you're trying to whisper but you end up shout - whispering cause you don't think the other person can hear you?Now, I told her, and everything fell silent and 2 seconds after the teacher walks in. But, she didn't say or do anything that would make me think that she heard us but being the paranoid person that I am - I can't help but worry! Is she gonna let me off the hook? I am a straight A student anyway. Plus,as you can see, I don't like to get into trouble too much...What do you think? Does she know? Or am I just worrying too much?