Oh quod I really feel for you. I was similar I just wanted to be at home with my things to get my mind around everything, I felt like I was losing control and everything was being controlled by other people.
Try not to fret too much, can you sleep in the car on the way this evening? Just to chill out a bit. Also, everything does have a way of working itself out, my OH is honestly as useful as a chocolate teapot and that is being kind but he has been reserving things at Argos and picking them up on his way home from work, we have decorated mostly in the evenings as he goes fishing at the weekend if I make any suggestions of DIY
You will get their, plus the things the baby actually needs are limited. We have been fussing about the nursery and tbh he won't be in it for a fair while.
I do remember it dawning on me that all the months of TTC had finally had a result, but then thinking oh shit I am going to have a tiny little person who I am completely responsible for....cue meltdown. I also starting thinking of all the things we wouldn't be able to do. BUT I've spent 30 years getting to this point, I am ready for it now I've got my mind around it. Although the head in sand approach is also amazing isn't it alex. 
alex I'm 27 weeks, seems early I know but I wanted to get everything done before I turn into a walrus.
Plus if we spend the money now I know how we stand financially and can try to work out savings wise what we need to cope on the crappy 135 quid a week when I'm on maternity. Plus I have serious OCD and like to have everything done.