Could it still be possible??

Kelly • Boymama of 3 💙
I am 6DPO and so exhausted. Feeling like I'm coming down with a cold or something. Light cramping/pulling since ovulation day(which I felt!!) cm has changed my thin, milky colored to now clear and semi wet. 
​I am worries bc just last night Dh took sperm check and it was negative so therefore I now feel like I'm just making up these symptoms in my head and setting myself up for disappointment. 
​When should I poas?