Few pointers - the furthest parts of the inset bit int he middle should be blurred to match the depth of field of the stock photo - the edges wouldn't be as crisp as they appear here. Also, the blur/smudge marks near these edges are quite visible - instead of looking to conceal your editing through the use of such tools, try t use something such as the Clone-stamp brush instead. When selected, hit alt and left click to select the area you want to 'source', then paint over the image where needed. It's really useful, and you should give it a try! Also consider a reflection of the Japanese writing on the glass rim below it for added realism.
Otherwise, this is a greta piece of work! Lovely concept, and I like the details!