Slightly worried

When I was pregnant with my first, I got my BFP at 10DPO and retested again at 12DPO with blazing positives. I also got my BFP this time at 10DPO, but I feel like my tests today at 12DPO aren’t as strong as last time. Also, I know you’re not supposed to test every day as it could take 48 hours for HCG to double but I’m worried that the FRER isn’t darker than yesterday’s. The Wondfo and pregmate seem to be a bit darker. Top pictures are yesterday, bottoms are from just now.