Faint line?

Megan

Could this be a chemical pregnancy? I started feeling off around Friday, so I took a test and it was vvvvfl. I took another one tonight because my breasts really started to feel tender, and this is what I got. I compared it to Friday's test, and it is slightly darker and pinker, but not by much.

My period is due Friday, so I would be around 10 dpo maybe?

Anyone have a test take a while to get darker?