Sourdough virgin

Just started my first foray into the art of sourdough and I'm a bit bothered it's going so quickly. I made the mix yesterday and it's already doubled in size and is definitely whiffy.

Is this normal?

I believe I must wait for it to start to fall back before I refresh it, and  by this rate I'll have a usable starter by Tuesday and might well be running alive with bread before the week is out!

Thanks for that Trillium - natural bacteria floating in the air? Does that infer my home is infected ins some way?   I used Paul Hollywood's method and added some grapes to get it going.  I've put it into a larger container and I'm going to chuck and feed it now.  Still not sure if I should let it collapse before feeding it, but my instinct says no, so that's the way I'm going - feed it while it still stands up

There's a long sourdough thread on here Catlar    Sourdough bread making gets a bit addictive 

You can find more threads if you search for two words: sour dough 

So it's all gone pearshaped for the moment - it's dead, so  I binned it and I'll start again, but I'll wait until I come back from England after Easter. I've got enough valid info now and it finally seems there are many ways to make this beast - the one constant seems to be organic flour - mine wasn't.

Organic flour here is usually about the same price as non so I buy it.   The organic flour is more suited to sourdough as the grain is not treated with chemical fertilisers etc etc and so  has more wild yeasts thriving on it, hence a better success rate when you light the touch paper    You can soon tell if it's working as you can clearly see a living breathing organism. It'll open the lid on the Tupperware no problem