Advice please

I'm going to the doctor tomorrow. I haven't gotten my period this month yet I keep hitting the "my period is late button" I was suppose to get it on the 6th of July at first but it still hasn't showed. My periods have always been irregular since I've had it, but irregular as in I bleed for extended time, I've never missed a period. My last period was on June 7th-14th that was the first time I've ever had it that short. In May I also had a HSG done to see if my tubes are open (they are). I've taken pregnancy tests and they have all been negative. And I do have some symptoms (but trying not to eat my hopes up) my question is : is it possible to have negative at home tests and be pregnant? Like can it only show on a blood test? My husband and I have been trying for 1.5 years and have been checked and told nothing is wrong. I just don't want to get my hopes up and be disappointed