Sorry about radio silence! thanks for all your advice and support, really helps.
In the end I kept his bed in our room, just moved it to the wall furthest away from our bed, before it was right next to our bed. We are in a 2-bed flat and DD sleeps in he other room so can't really put him in there. My plan was to put him in the living room, but then thought better of it, because he can't be there on a regular basis. I am thinking why shouldn't he be able to learn to self settle in his cot while being in the room with us? If he learns that we will not pick him up, he should learn to settle, surely?
He cried for 10 mins when I first put him down at 6.30 and then fell asleep as he was so exhausted. Then woke up at 11pm. I reassured him and let him cry for 5, then 7 and so on minutes. I got out of bed and patted / caressed him and each time it soothed him, as soon as I stopped he went right back to crying. I didn't look at the clock towards the end but would say he cried for about an entire hour.
Then he woke again around 3.30 - 4am I would say, and it was all over again, crying for a bit more than an hour.
The second time he cried he woke up DD who then started crying and came into our bed where she stayed until she woke up at 6am (shudder). Don't mind that though as she's normally a very good sleeper and usually always stays in her own bed the whole night through. But this was one of the things I feared about CC - how it would affect her.
I got a bad cold and it go worse over night so am now down with sore throat and shivers etc. So wondering if I'll be able to keep it up tonight.
The other thing I didn't plan for properly was how much my boobs would leak, of course as they're used to night time feeding, I hadn't put on a bra or maternity pads and was so tired and disorganised I just ended up changing T-shirt 8 times! The more he cried the more my boobs leaked. Nature really not helping here. Think being soaking wet half the night made me more ill, too, Jeez, not having the best of luck.
Also, I fear I bungled it at the end, as when he finally woke for the day at 7am I took him into bed and breastfed him there for a while before getting up. I had decided that I would NOT do this and would BF him on the sofa in the living room for the first feed of the day, but I was so exhausted and ill with this cold that I just couldn't get out of bed, ugh. Hope this has not rendered the whole process in vain. It was pure heaven to finally be able to hold his little body and cuddle him though. Damn, this is so hard.