Need other eyes please

Rashmi

Please check....

pic1 is 12dpo within 5 mins

pic2 is 12dpo after 10 mins

pic3 4 is 15dpo within 5 mins

pic 5 6 is 15 dpo after 5 mins

The line didn't come immediately but within the time mentioned on the kit.... is there a difference between 12 and 15 dpo? I am tensed as it should get darker in 72 hrs right? This is my first pregnancy so have no experience.... Need everyone's support and guidance please