Help any advice would be great ❤️

So Its been 5 weeks and 3 days since my last period. On my glow calendar it says it's been 19 since my period was supposed to start. I am having light cramps like my period is goin to come on but it still hasn't. I have itchy breast light headaches. I'm tired all the time and I do have mood swings. So I took 3 test and all r negative. Has this happened to anyone? Is this maybe a sign of it not being long enough to tell yet?? I am making an appointment for next week. But someone please give me some feed back ❤️❤️