Weeks on digital HPT not changing..has something happened?

I am anxiously awaiting my Dr appointment on Oct 9. I tested when I was late for my AF on sept 20 and got pregnant 2-3 weeks but my math suggested it was closer to 4 weeks... I used afternoon pee so assumed it was because it was diluted. I felt pregnacy symptoms all last week but this week I feel good... I don't feel pregnant at all except extremely sore boobs and still peering all the time. I decided to take another digital test as I had bought a few and thought I might as well use them right... So now I believe I should be around 6 weeks. I took the test with second morning pee ( I forgot first thing this am... Another symptom I am having) but hadn't had anything to drink yet so thought it would just be from not emptying my bladder fully before. Anyways the test says pregnant but still comes up 2-3 weeks so now I am freaking out? Has anyone had this? Does it mean something has happened? Wouldn't I be getting spotting or bleeding if it has? I haven't had a single spot of blood since my AF in August... Not any spotting or anything...