I would call the line manager again, be a "squeaky wheel" and let her know things have gotten worse, ask again are there any spots/emergency spots, whatever open.

I would also look at my list and start to concentrate on some of the items that the therapist can't help with, that are your responsibility, like making sure you eat well, create good sleep habits, get up on time and do some homework and revising each day. I would use the positive action of calling the therapist's office and knowing that you will get into see your therapist as soon as it can be arranged and have done that for yourself to motivate you until you do see her.

I'd also make a list of the things your therapist might be able to help you with, the thoughts and sleeping difficulty reasons you cannot control as easily by yourself (anxious thoughts at night, too much anxious thought during the day making you tired because you feel you are working "hard" on it but getting nowhere, etc.) and see if I could use my sense of hope that she will help you with those things, feel that she will still there for you. The more you can mobilize your own thoughts, hopes and actions (instead of just fears and anxieties) the more things will start looking up.

If I could not get in to see the therapist within another couple weeks, I would call my medical doctor, go talk to him and see if he had anything to offer like a mild sleeping aid or tests to make sure my hormones and vitamin levels are all good and maybe some suggestions on how to take better care of myself while I wait to see the therapist.