frustrated! help!

Im on cycle day 36...19 dpo...have taken 3 pregnancy test - all negative! Im very regular. I went back a whole year and my longest cycle was 34 days. I have been feeling symptoms, but dont want to get hopes up so I dismiss them as PMS. The light cramping I’ve been having feels different though. I’ve had these cramps for about 5 days-on and off, lighter, and lower in pelvic area....dizziness and nausea too...sore and swollen boobs...also something i had never experienced is a lot of CM - to the point I thought AF had arrived. how much longer should i wait to get blood test done? any similar stories??