It used to be shazzles if a doctor wrote a note and said you were not fit to work that it would be enough. In the nhs we are interviewed every time we are off sick. They say it is to help I dont think so. I am a worrier too and to avoid these silly interviews, even though I am never off sick I went to work, what was a cold then went to my chest and I ended up off longer, and really ill.
If you should lose your job, and only my opinion it might be possible for your Ip to give you a payment holiday for a couple of months in which time hopefully you can get another job. Sciatic pain is awful I suffer myself on and off, another thing 28years of nursing has done for me. Ooh I am having a moan now.
Go back to your doctors honey and tell him the tablets are not working. Your gp can change them for something else. Work wise it is up to you, I dont know what you do, some may be better sitting others are better up on their feet with back pain, but in all honesty you should take time off and get better because in the long run your sickness will be shorter, go to work and damage it more and you end up off longer.
I am rattling a bit ,as I quite often do, do what is best for you dont make it worse.
Ang