Signs of pregnancy before BFP

Janyll
Ok possibly tmi here but going to list all the symptoms I've had since 4dpo. Please can anyone tell me if this could be my imagination?!
​Headaches
​Cramps
​Fatigue
​Tiny nipple discharge when squeezed
​Very sore breasts
​Sharp shooting pain in right breast
​Moody
​Lower back pain 
​Could I be bringing this on myself?! 
​Now at 16dpo and was negative on Monday. Af due on Friday!