Line progression on different tests

Kat

Anyone else experience very faint lines or very little line progression on the cheap tests? These are the pregable brand and I feel like all of my lines look to same. Took a test on Saturday at 13dpo and I threw it out after only a few mins cause I swore it was negative. Took a test yesterday afternoon at 15dpo just to see and I got the first picture. I was shocked. This morning at 16dpo I tested with fmu and the second pic was the darkest the strip got. But I also did two clear blue tests with the same urine, pic 3…I’m so confused, anyone else experience this?? Ordered new tests and going to keep checking every day