Sounds like you have a typical spaniel pup on your hands. Did you research spaniels, especially working cockers? They are certainly not for the faint hearted, lol! Lots of people dont realise there are two different strains of cocker which are significantly different - 'working' and 'show', the show strain being lower energy generally.
Echo momsters post. Ours is also 11 months old. He is everything everyone warned us about and that we already expected from our research...mad as a box of frogs, high energy, needs loads of stimulation and company, but is very easy to train, eager to please, affectionate, comical and a spaniel through and through. Wouldnt have him any other way. After a lot of thought we decided on him following a recommendation from a friend who has/had two (having unfortunately now lost one to cancer) her remaining one being six now.
Incidentally it is a spaniel ''thing'' to pinch socks. As is grabbing the nearest item and strutting about with a vigorously wagging rear end to greet any visitor/family member coming downstairs, entering the room, etc. Most spaniel owners find it endearing - spaniels are not in general destructive, they just like to ''acquire'' things.
We also walk ours 3 times a day, two of these are off lead. At the moment this totals approx 2 hours a day. Now he is approaching a year old I am considering looking into agility/advanced training of some sort. To be honest we didnt bother with puppy classes as we found him a dream to teach the basics to ourselves, however if you have a good local one it may be of benefit to you for stimulation/socialisation purposes.
Unfortunately neither I nor any spaniel owner will tell you that she will 'calm down' any time soon, a spaniel is a spaniel forevermore! however from the several cocker owners we now know, they do seem to reach a bit of a plateau at around 18 months or so (once adolescence is well and truly out of the way)
I do hope you work out what is best for all of you, good luck whatever you decide.