No no, you are not garbling, I do agree with smee though and if you want to go ahead with the interview then set an hour?s pre max, and stick to it then move on and relax. If you really feel that you won?t do your best tomorrow then you have 2 options, go and ?wing it?, or you really feel you can?t do what you need too then cancel and don?t feel bad about it, you could extend the truth if you have to if you are worried about sounding flakey?
If you think you have got PND could it be worth calling your health visitor? It saves you having to get into the doctors?.I had PND and my HV came out to me, she was very good and referred me, plus she got me a doctor?s appointment quicker. It was all a bit grim for a while (I felt crap being told that I had it, but at least then I could move along and get better).
Good luck and don?t stressed if you have to cancel?.good luck if you do go.