7w 5d fading test line?

I’m 7w 5d and this morning just for the heck of it I took a pregnancy test and the line was much less dark than before. This will be my 6th pregnancy with only 1 surviving. Now I’m starting to worry that maybe I’m not going to have this baby ☹️ does this happen? Does it fade around 8weeks? I’ve had little symptoms mostly nausea and my boobs hurting in a bra but not much after that… I go for another ultrasound tomorrow but I’m a little worried. I also tried the diluting thing for the hook affect and it definitely is darker so I’m trying to convince my self I’m worried for no reason. Top is non diluted bottom was with water.