what to do

Jessica
So this month was a weird ovulation/fertile time for me. I missed it with the opks but based on my deduction I did Bd on or close to peak.  But because I can't tell when I really ovulated, I have 2 apps telling me my upcoming period is either the 21 or 25.
Today is possibly 10dpo
So since then I've had on and off sore back, my breasts are seriously sore, left side twinges that are off and on, gassy, tired but also can't sleep and what maybe feels like mild heartburn. 
Sigh, so I go to the bathroom to pee and besides having super creamy cm, it appears to have a speck of blood in it, like a pen mark.  I wipe again and there's a smaller one on the tissue.  
So my ladies, I'm petrified to take a test this early and scared that with this it'll be negative and I'll be heartbroken once again!!