I would deffinately advise a change of food. Bakers is pretty rubbish stuff, and not something i would ever feed or reccomend for a growing pup.
I wouldn't feed Eukanuba either, but each to thier own. If price is a factor in what you choose, then id say look online at
http://www.csjk9.com/range/ thier 'champ' range is very affordable and has produced good results for dogs of people i know.
It may be that he could have picked a bug up and his looseness is not diet related, but im pretty sure if my three were fed on bakers they would be pretty loose as well itchy and probably rather hyper.
Even if it turns out the problem is not diet related, i would still advise switching foods, springers are enough of a handfull without being fed a food full of additives and colourings.
Hope the little man perks ups soon.