Should I test?!

Okay so I have 4 days till expected period (Friday).. and I'm not sure how many dpo.. but I legit feel like I know, I just need a test to tell me! .. I've had light cramping on and off for a while, I've been having dizzy spells and random headaches.. all things that I had with my past 2 pregnancies.. but would it be too early to get a line?! Help! I wanna run to the store tonight! haha