I'm sorry that I don't have anything useful to say, except that I know EXACLY how you feel. Except I'm in my third year of it, not third semester. My centre is meant to be a short term one too and I constantly panic to my T about someone one day saying that I can't see her anymore and everytime, she tells me that it is her discretion and that lots of students are short term but there have been a few longer ones, even four and five year ones. It really helps me to be able to hear reassurance from my T, maybe it would help you too? It doesn't even have to be a question you ask, but just mention how you're concerned about where things stand. I know it's a really awkward conversation to start but it really really helps.
And I worry about the same thing with the receptionist because she knows me by name and face (and the assistant receptionists changes quite a bit but it never takes them long to learn my name and face too!) but she's always been very sweet to me and I worry about it less now!

First sessions are always the hardest because there's always been so much that's happened in the break and I just get so overwhelmed because it all causes me a lot of anxiety or pent up emotions but I can't explain everything in one session. So I always find the first session after a break to be one of the hardest. During those times, I usually tell her that I just have too much in my head and I can't get it out all and in order to be able to explain it to her. And she helps me make sense with it.

I'm sorry I can't help you with anything, I just wanted you to know that I know exactly how you feel and that I'll be going through the same thing starting on Monday too!