You cannot check actual clicks in the camera, but it's in the metadata and Nikon has a policy of never resetting it, even when the shutter is replaced. You do not have to upload a photo if you have Photoshop or any other tool that displays full metadata. In Ps open the image and then choose File->File Info. In the Raw Data tab will be a row with Image Number. The number next to that is your total number of clicks.
I second Hark's article on what to check. Suffice it to say that the cleaner the camera, the less I'd worry about clicks. A well cared for machine will long outlast an abused one almost every time.