Hi I'm having similar probelms in getting a refund.
The order process was fine and delivery was prompt but the product I recieved was (like you) not what I thought I'd ordered so I got a return number and returned it as instructed.
That was just under 2 weeks ago and when I phoned today they are saying they've not recieved it yet so they can't refund me.
Like you I'm slightly concerned and would be interested to know if/when you get a refund.
The person I spoke to on the phone earlier was really helpful but it still seems strange that it's taking so long to refund me.
I will check back with them later in the week as they suggested.