Missed period

Jane
Hi everyone, I wonder if anyone could give me any advice, I was due on 1st/2nd of July and AF still hasn't came. I've took 2 FRER tests one with FMU but both negative however when I held them up to the light they had what looked like a 2nd line in the window which was very faint. These tests were took on Thurs and Fri. I've had no symptoms except 2 weeks ago when I had slight cramps but that's normal for me before AF. I've read online not to worry about 1 month with no period, it's when it gets to 3 to worry but I'm a worrier and can't stop myself for thinking about it which won't help. I haven't been stressed so don't know what's happened. Thanks in advance.