I need serious help!

Ok I found out last Friday I was pregnant so I set up appt to go to Dr on Monday. Took tests on Saturday and Sunday and they was negative but went to Dr on Monday it was positive but just barely at 6. Went back to Dr on Wednesday and it was just 8 so they want me to come back next week to check them again. Idk what's going on. I'm not spotting, bleeding, or cramping. I just get a little pressure every now and then. I have continued to pee on sticks everyday to see if I've miscarried yet and I still have two lines and it's been a week and 2 days now since I first tested. Can someone tell me what's going on? Am I still pregnant?