Do you have any symptoms? I have also been worried because I got my BFP on many different tests but they arent super dark. They have gotten darker over the past couple of days though. I think different batches of tests and how much liquid you drank ect comes into account. Im not overly worried right now because I have a dull pain in my uterus and boobs are tingling on and off and are sore to touch.

You should see a doctor asap to ease your mind.