Too much for one brain?

I have to admit I am feeling a little bit overwhelmed today and what makes matters worse is that it is all my own doing!
Not content with writing my novel I registered with http://www.shortbreadstories.co.uk/ last week and started writing short stories as well. All well and good I thought. Keep my mind ticking over I thought. Good for the creative juices I thought. But alas! I have now hit 50,000 words on the novel front and am having to re-read what has gone before because I have, literally, lost the plot!
I have one short story in the editing queue, another in draft form registered on the website whilst another is buzzing around in my head demanding to be written.
Something has got to give. Hasn't it? I'm not so sure. One idea sparks off another and then there is a chain reaction which gives rise to better and better ideas, storylines, dialogue, characters, plot twists...
What I really need to learn now is how to squeeze 28 hours in to a 24 hour time frame - then I really will have the perfect formula for cramming it all in!
H-J