Hiya hun,

Sorry you find yourself in this stressful situation! There's really no way of knowing until you can do an HPT. 18/25 is really early still, even if you ovulated on CD 12 or 13 (which is very early but if you have a 25 day cycle I guess it's possible) then you'd only be 5 or 6DPO, you won't get an accurate result until more like 10 or 12DPO. You could test, but it might give you a false negative.