Hey Geez,

If you don't hear from her in the next few hours or by this evening then you could always ring first thing tomorrow. Or if it's worrying you maybe just ring now and say you sent and email but worried she wouldn't get it. You have every right to ask to take the appointment, she did offer you it. If she's going on holiday in a few weeks then take as much support you can now. It can often take more courage to ask for help than to go it alone.