What do I do??

Sooo... my hubby 'slipped up' during the peak of my ovulation. (Sep 2) I was supposed to start my period on the 18th, but instead I was visited yesterday by a thin, white discharge. I thought it was my period bc my underwear were wet, but nope! Had no smell.. wasn't sticky, almost milky. 7 days later exactly (according to my logs on here) i had mild cramping that was very period-like, but not nearly as intense. My breasts have been sore, like dull aches and my nipples have been a little sensitive and kind of itchy. I've had headaches the past 3 days.. I never have headaches. I took this test this morning.. a $1 DG test and got a negative. It shouldn't be too soon to take it if I've missed my period, right? Should I get a better test? Maybe my period is his messing with me? I have been under some extra stress lately. Maybe I'm giving myself symptoms?? HELP! ((Btw.. I know it's a blurry pic, my phone is cheap and doesn't focus right))