I am not sure what the status of medical marijuana is in Australia.
As its use has been more widely accepted in the US, there have been many studies that show good outcomes in PTSD treatment.
It is not in my current medicine cabinet, but in years past I found it helpful in self-treating similar symptoms to yours.

So on your own or with professional guidance, it is something to research and consider.

And if medical marijuana isn't accessible, CBD oil is an effective alternative.

Medical marijuana was legalised in Australia very recently but only for a limited range of conditions (mainly terminal conditions) but it is relatively tolerated by police as long as you're not driving.
Nevertheless I do use it. My medical team know and are fine with it. There are no prescription drugs available which can help my symptoms. It helps stop the shaking, eases the physical pain, and softens the background fear.

I'd like to try CBD oil, but there are no derivative products available here either.

Re Lumberjim's post - I have not been able to find a specific PTSD forum and don't even know how to find one (my google skills have gone out the window too).

I have had discussions with people on some Facebook pages but they have been US dominated, and the treatment available there is quite different to Australia.

I have not had a brain scan, but there has been no doubt for any of the medical/science people I've talked to, that I do have PTSD, based on the physical as well as psychological symptoms. But what I have been able to read about it makes sense of what I'm experiencing.

My sense of smell is not noticably different, but my sense of taste is. E.g. I never liked beer before this. I used to like a wide variety of global food but now prefer bland foods.

A startling change was my ability to tolerate extreme temperatures. I used to struggle with anything over about 32C, or below zeroC. I flew from a hot Australian summer (no problems - literally no sweat) to northern Sweden in winter (-30C) and also had no issues. I refused to wear a hat (needed to hear who was around me) and had no problems. Then I flew to northern Thailand (around 40C and extremely humid) and again, no problems, no sweat, and I often left the aircon turned off in my room. It was the strangest thing.