No, it was not an emergency exit seat, and yes I paid extra for it, it was the last row of seats on the plane and only two seats, on the outward journey which was through the day I had the aisle seat and I asked the passenger next to me at the window seat if she paid extra for it, she said she never booked her seat at all.
I booked the window seat on the inward journey as it was a night flight and I wanted a seat and paid extra.