Should I test?

AF due tomorrow.... Cervix is high and open(I can basically stick a finger in there, lol) and at least one time for the past three/four days when I wipe there is a nice stretch of egg white(clear sticky and stretchy) discharge.....
If I test tonight with a first response early result test, IF I was pregnant, would it show, or do I have to wait/should I wait until tomorrow AM. 
~I've taken cheapies mid day and they are negative~