indent line? please help

I took this test with my second urine for the morning. It was still pretty strong as I hadn't ate or drank. When I looked at it in the light I could see a line. I made it negative so I could see it better. Is this just an indent line? The line had no colour to it, it was only white. 
Can you see it the line? Do you think it's an indent. 
Keep in mind I would be about 4 month pregnant if I was pregnant so I'm not trying to early... Surly if I was the line would be darker and have colour to it? 

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