Black Spots/Smudge on IPhone 5S Camera Lense

So I just got the IPhone 5s about 2 weeks ago. Prior to week 2 I took my phone back into my service provider explaining to them that there seemed to be 2 large (large in comparison to the camera lense) smudges on the inside of the back camera lense.

I was also experiencing signal issues, which was my main reason for going there. The employee explained to me that those are sensors for the camera, and then went on to figure out my signal problems.

I got caught up in the conversation, and was too satisfied with the signal fix, that I didn't think of checking the other IPhones on display in the store, to see if the black spot/smudge I was suspicious about were really camera sensors.

As another week past, I kept on noticing the smudge underneath the camera lense. After doing some research, and looking harder at this smudge (sensor) I feel like it's a defect.

It basically looks like someone put a fingerprint on the inside, at the very top of the lense. I've tried cleaning it, but it still stays. I'm pretty disappointed. One of the reasons I got this phone was because of the speed/camera. I'm not looking forward to having to make more then 1 trip to the store to figure this all out.

This is my first apple product, so any advice would be nice.

[Just a note, I know there's 2 sensors on the front of the phone for the camera. That's not what I'm referencing]