This might be helpful! www.today.com/health/healt... Generally the consensus about ambiguous tests is that if you can make out a line at all, you should consider it a positive test (and positive means you are likely contagious and should isolate or wear a good mask if you have to be around others)
Certainly to be on the safe side, this is an option!
I just recovered from COVID and I’m fairly convinced that the last few days I was testing positive, I was not infectious. However, the rapid tests are just looking for antigen, not infectious virus.
Yeah, the way these work it’s basically like a pregnancy test. Any line at all counts and false positives are really unlikely. The only caveat is that past the half hour window for reading the results, you can get dye bleed that could be mistaken for a line.