When should i test again

Cassie • Momma of Two Graci 5-7-15 Graeson 9-7-16! Angel Momma of Two Nov 2015 and Twin B Jan 19 2016!
Ive tested the past three day and last tuesday all BFN i am three days late for my period had period like cramps last night for about two hours and some off and on sore boobs off and on and milky white pasty cm is this pms or am i pregnant??