You're all amazing, thank you. I need to figure out who's the right person to call (especially over Christmas with everything shut etc) given I'm straddling 2 different countries' healthcare systems etc. I don't know if I do have PND but I could well have the startings/roots of it, if that makes sense? Like if I didn't watch myself if could very well turn into depression. I had depression in the past so I know the warning flags.
Ok so after all that - DS slept through to 6am. 
A few snuffles at 2am and 4am but he stayed asleep. So that means he slept from about 9.30pm to 6am. So I was feeling confused but proud of DS and gave him a bottle at 6am which he hungrily slurped. Too eagerly, unfortunately, as he promptly threw up all over himself afterwards... like a reallly bad vom, covered his face with vomit while he was lying down and it got in his eyes etc :( poor thing. I had to give him another bath and a cuddle he was so upset with himself for vomiting, and then he went to sleep. WTF, babies are weird. So having a very very very very strong cup of coffee with shaky hands.
yomping I'm going to check out those books. My mother had a very very violent temper and I don't want to repeat that. I was so frightened my whole childhood of my mother and I don't want DS to ever feel like that. I was horrified when I raised my hand to throw that muslin as I just recognised my own mother in myself. Just awful.
huffle shit, what am I complaining about when you're busy managing the stress of your own business! Arrrgh re your receptionist, but yay for your DH being able to step in to help where he can. Can you possibly express on the morning eg of the interviews and arrange for DH/friend/family member to look after DS? Eg schedule interviews so you can express quickly every 2-3 hours between interviews. It's ok not to sterilise expressing stuff between every single expression, I was told.
Another day... time to soldier on. DH arrives on Sunday morning. He is really feeling bad that he's not here to help me.
Sigh as for DMIL's comments - she is a lot bit batty now she's in her late 60s - DH and I have raised that she needs to think before she talks as she doesn't realise she's being insensitive but she honestly just forgets. She is 70% of the time useful, 30% the time a total pain in the ass. I could keep on and on at her like a stuck record that she's being insensitive and upsetting me, she would apologise profusely but then 2 hours later forget and say the same thing.... Am finding DFIL to be really good right now. DMIL is all like "ohhhh aren't babies sweetness and light blah blah blah" but DFIL is like "he's great fun, but yeah it's a total pain in the ass when he cries constantly, so confusing for you. But you're doing great". Which is what I need to hear to cope, rather than all this "ohhhh who cares if he vomits 5 times in a row and shits on your hand and won't go to sleep, look at his little ickle button nose!" As in, an acknowledgement that sane rational adults don't have unlimited patience for crying/vomiting/upset babies.
DMIL's SIL is here right now and she figured I had a rough night (even though she joined in the jovial mockery last night). Similar to what woolybob said, she said that you could see (but never of course excuse) how people could hurt their babies when you are tired and at the end of your tether when they are being colicky. I remember there was a few years ago and at the time I was like "who would ever be tempted to shake their baby?! It's just a baby! How can their crying be THAT upsetting?? Just go make a cup of tea..." - ohhhh boy have I had an education since then!
So in summary: THANK YOU all and YAY FOR OTHER PARENTS BEING HONEST as a coping mechanism. This perfect patient mother shite can fuck right off to fuck off town, and when it gets there it can fuck off some more.