What's going on?

I had a clear faint positive at 9dpo(seen in this photo). Fast forward today 10dpo. I tested twice and the line seems to be even lighter or not there at all. Could it have been a false positive or is there something wrong? Has anyone experienced this? I'm scared as I had an early miscarriage in October so this is really freaking me out and doesn't make any sense. The lines are meant to get darker everyday? Why would I have a clear second line at 9dpo and then almost nothing at 10dpo?