Reply To: after date
It’s not a good sign that she didn’t respond. If she had responded, that would have shown interest. But then again, you did say you would contact her when you got back. She was expecting to hear from you in three weeks, not three days. So I wouldn’t necessarily take this as a bad sign.
In any case, this is why in situations like this, I like to make sure an email like this doesn’t necessarily need a response, in case she doesn’t response. In other words, don’t ask questions in the email. Just make statements. If she doesn’t respond, then you can still contact her later. But if you do ask a question and she doesn’t respond, you’re kinda screwed. On top of that, questions tend to come off as needy.
Whether or not she’s interested, I would just wait until you get back from your trip to contact her. I would definitely not text her during her trip, not after you said you would text her when you got back.