OB appt tomorrow.

I'm nervous about my OB appt tomorrow. They are going to confirm my pregnancy, I'm 6w3d today but my tests have been very faint, hard to determine if they are positive. My first pregnancy, i didnt show positive until i was 7weeks along so im afraid they would get a negative result. I am totally pregnant, all the symptoms are there and have had a missed period. I have to be pregnany...right?