I really like your first shot, but you've got some spots on your sensor. This might be dust. Some cameras will splatter oil spots (they lubricate the hinge for the mirror and if it's got too much oil or it gets a bit warm and the oil thins with the temps then it can throw some splatter.)
Take a photo of a plain "white" wall at a high f-stop and (e.g. f/22) and it should be easy to spot.
I've annotated your image to show the spots. This image is a bit small but the spots are easy to see at Flickr where your image is much larger.
I just noticed one more spot in the upper-right corner than I missed marking. There are likely more spots lower in the frame but these be hard to spot. It's easiest to see on an image of a plain white background and especially at a high f-stop.