Hello, so sorry to hear your situation. Mine was very similar, diagnosis and number of weeks. It was my second pregnancy, I already had a daughter. I was devastated and it had a huge emotional toll but physically the tfmr was fine. Well, not too bad anyway.
I had no discernible effects from the tablets and when I went in, it all happened 4 or 5 hours after the pessary went in. I had no pain, had a top up tablet dose 2 hours after the pessary, sometime after that I had period cramps which got quite painful so I asked for pain relief and was given cocodamol, not sure what strength.
Pain stayed like that until if happened, was very sudden, tmi but I thought I needed a poo and it was the baby.
Placenta got a bit stuck and they had to do an internal to remove it, other option was surgery.
I bled for about 6 weeks and was pregnant after 4 months.
It didn't feel labour, nowhere near as bad, felt much more like very severe period pain, not unbearable at all like labour. I read a magazine through most of the cramps.
They wanted me to stay in but did let me out asking as i came back the next day for anti D and some other stuff. Forms I think.
They'll ask if you want to see your baby and what to do with their remains.
This board on here is brilliant:-
www.mumsnet.com/Talk/antenatal_tests_choices
Loads of similar stories and if you start a new thread on there repeating your post from here I bet you'll get loads if great info and support. I spent a lots of time on there with mine, crying my eyes out asking tmi questions and reading loads of old threads. You might see mine in there from 2013, I was called Bigcorriefan then.
Sorry again, it's the hardest thing I've ever been through. The worst part was between diagnosis and the tfmr for me.
I have had 2 more babies since, hopefully you'll be ready to try again at some point x