Feeling PMS Symptoms for 2 weeks at at time or more

Biancakara
Hi guys usually my period is every 6 weeks... Lady cycle it was about 8 1/2 weeks and now I am going on 9 weeks.  My PMS symptoms are horrible breast specifically.... Also pressure below the belt.  I took 2 test negative... I feel crazy cause I cannot tell what's going on... Anyone ever have this?