Sorry to hear you going through it mate.
Strong Codeine Linctus will help with the coughing fits. It's horrible stuff and will make you feel a little spaced out, but it does have an impact.
Wish I could tell you when coughing stops, but now almost a month for me, everyone is different.
Just don't do any strenuous exercise (whatsoever) even if you start to feel up to it - it will remind you very quickly that your lungs needs a sustained holiday.
I did find some short temporary relief sleeping on my front to try and help my lungs, but anybody with serious coughing will tell you that it becomes too uncomfortable after ten minutes or so.
Get a soluble Vit C and Zinc multivitamin tablet in you each morning, dose between paracetamol and ibuprofen, keep speaking to your GP if you bring up any blood in coughing, which I did, even if just to put your mind at rest.
And keep resting, loads of it. I intend to take the entire month off. I'd not had a day off work or a holiday for a couple of years and my immune system was clearly wanting to tap me on the shoulder and let me know I was running on empty.
Best wishes.