Covid test/pink smudge

[hereforwhatever]

Coming down with a cold but mainly it's a sore throat. Just before I headed out to the pharmacy for some meds, thought I'd take a Covid test. It's just got a very little pink smudge under the first line.

I'm thinking this is probably negative? Any thoughts?

Is that taken at the fully developed time? Some I have give a big pink smudge like that but it vanishes after several minutes.