I`m currently going through the same. I tested dpo 12 got a faint test tested for the next few days tests got darker, only IC didnt get very dark but a defo line. Took a clearblue digi which said pregnant 2-3 weeks. Took a test yesterday expecting to see a dark line on a IC and only a very faint line, rushed to shops and got a clear blue but not the one that tells me how far on I am (brought my mistake). Ive convinced myself its gone wrong, surly the lines should be getting darker not fainter?
FX for you, sorry for my rant. Feeling bit hopeless