Shouldn’t I get a darker pregnancy test every day?

Ay

Hi Girls

I had a positive pregnancy test few days a go.

The top test is todays one and the second one is for few days a go (2 or 3 ) I don’t remember well.

I expected to get a more strong line than few days a go but it looks the same.

Is this normal?

I am about 4 weeks and 6 days I believe.