Wild Starter???

Ok... so I brew yesterday... I made an extra 2000ml of wort with my grains after my initial beer was going... and boiled that extra wort for 20 mins and put it in my Erlenmeyer flask... I put a stopper with a airlock on it... and was going to just pitch the yeast tonight...

When I went down tonight to pitch the yeast... I noticed that my wort in the flask had started to ferment...

Just to answer some quick questions.

1. yes I sanitized the flask, stopper & Airlock

2. it isn't fermenting vigorously... just had a little foam forming at the top and the airlock is bubbling once a minute or more...


SHOULD I PITCH MY YEAST AND TRY AND MAKE A STARTER?

I wouldn't trust wort that's been sitting around for a day. Make yourself another starter.