4 dpo

In

Hey there, 4 dpo but not feeling quite happy. I just hated opk tests and started using bbt, got me less anxiety and stress. I'm feeling like crap rn, my nipples are sore from the first days of March, but why? I experienced pain in my back in the last half an hour (near the kidneys). Another app says I should test tomorrow as my last cycle was 41 days, but Glow and another one say test in 10 days. What do you think? Thank you