Pain relief I am going for gas and air and hoping for water birth. Pethadine sounds a bit dodgy to me. Can't have an epidural at the birthing centre so that's about it really.
I too am experiencing plenty of aches and pains (especially low in pelvis and everywhere in my back) and the diarrhoea has given way to constipation. Just spent two nights at my MiL's sleeping one sofabed which horrified most people in my yoga class! It was bloody uncomfortable and I have been hurting ever since.
Also getting fed up of comments. Went to visit s friend if my husband's who just wouldn't shut up with the 'it will be hell and you will never get any sleep ever again' line. DH had been in an affectionate, enthusiastic mood up until then but she well and truly crushed it 
However, I also got 'make sure you keep going with your lives and don't revolve everything round the baby' from MiL (subtext= 'I want to come and stay at your house a day or two after he's born and I bloody well think you should make the effort').
I am trying to keep calm about it and not take things to heart but as many of you have said people's insensitivity can be astounding. My worst was DH's aunt at Christmas after playing with my DH's nephew... 'such a lovely boy, yours has so much to live up to'. Great thing to say to an expectant mother!
Ah well, we're the ones having the babies! We will do it our way and that will be right!
37+3 and off for a paracetamol and a hot chocolate.