My husband and I are trying to get pregnant and I used one of those online ovulation calculators and it said I would be ovulating the 22nd through the 27th. We've had sex every day and the last two days my boobs have been really sore and this morning I woke up with really bad cramps in my lower middle and left side of my abdomin. I never really have cramps with my cycle so I'm not sure if it's just normal pre-period cramps. Could this be implantation cramping? and how soon could I accurately take a hpt?