Plant Food Help ?

How you doing, ive planted my germinated seeds about 2-3 days ago and was wondering when the right time to start feeding is ? I read somewhere that if you start feeding them too early its bad ? So i was going to wait about 2 weeks or so until they get a bit bigger.
I had a drive down to B&Q today looking what plant food they had to offer and they had quite a wide range. With me being a first time grower:-

Should i go for the Miracle-Grow Slow Release plant food ? which are them little pellet like plant food http://www.diy.com/diy/jsp/bq/nav.jsp?action=detail&fh_secondid=9413586&fh_location=//catalog01/en_GB/categories<{9372012}/categories<{9372020}/categories<{9372095}/specificationsProductType=plant_care/specificationsSpecificProductType=plant___vegetable_food

or should i just go for Concentrate Multipurpose plant food what you have to water down ? http://www.diy.com/diy/jsp/bq/nav.jsp?action=detail&fh_secondid=10777722&fh_location=//catalog01/en_GB/categories<{9372012}/categories<{9372020}/categories<{9372095}/specificationsProductType=plant_care/specificationsSpecificProductType=plant___vegetable_food

Thanks for any help, i know its a newbie question but hey, gotta start somewhere!
Cheers, Lee6.

look mate you need to go to your local hydro shop and get proper feed if you want good strong weed. if you have planted into small pots you should just water and spray to keep humidity up. when your plants have rooted those pots move them to 11ltr + as more roots mean mean more bud. at this stage you should use root stimulater and soil stim. look up rhizotonic on ebay this stuff is great its like anti biotics for plants and builds up strength for root and plant helping prevent disease hope this helps..

thanks on that info it helped quite alot. but will normal plant food work or not ?

i used all purpose plant food before. works fine. it was 15 35 15

yeh man ok well as long as it works just aswell. cheers for the info mate