Late on my period!!? 😕

Kh

So i was suppose to have my period towards the beginning of this month (around the 10th) and as of today its the 18th of November, me and my husband have been trying recently like 2-3 months and this morning i took a pregnancy test and it said negative ( this is also my 3rd time taking a test with in the 2-3 months). We seriously cant stop hoping that im pregnant but ive been cramping threw out the days but not spotting or anything. I can always tell when im going to start my period because im a raging bitch lol, i have delt with alot of family stress this month, which is making me think that maybe its affected my cycle but when that happenes its not longer than a day or 2 that my period would start a day later. So im wondering could i be pregnant and test just cant detect it?! and is it to early to tell? ? has anyone else experienced this before? is it possible to be pregnant n pregnancy test cant detect it?! Any words of advice or comments would be greatly appriciated ☺