Pixi, please feel free to talk us through it whenever. I know you don't always want to burden your dh with it all, so if you can't talk on here, well, where can you? Struggling with four little ones on your own must be tough enough, but to be pregnant and not getting sleep is hell.
Here's an idea for all the stuck indoors mummies - play an all-over the house hide and seek. We spent ages doing it yesterday and its a great way to get them active and happy without going out. I always used to have to hide with the dts (with my hands over their mouths to stop them talking!) or count with the one who was supposed to be counting, but now they get it and do it themselves and its great fun. Even if they keep hiding in the same three places, somehow the thrill of it doesn't seem to wear off.
Or, with the older ones, send them on hunts - either hide certain toys so they have to find them, or say 'first one to bring me a sock/spoon/pillow' - you don't even have to get off your ass to do that one!
And then (particularly you Pixi), you can get the duvets out and all cuddle up in front of a DVD, hopefully sneaking in a crafty snooze if they'll sit still enough . I used to do it all the time when I was pregnant.
As long as they have some active time in the day, then I justify the TV watching.