Abnormal periods and pregnancy tests?

by Liz
(California)

My last period was abnormal, now this one is 4 days late. Can i be pregnant? I had unprotected sex a week before my last period (we used the pullout method). I then had a weird period a few days later. Normally i have my period for 3 days heavy the first two then really light the last day. My last period I was heavy one day and then it was gone the next, then I spotted another day and then heavy for one more. It was abnormal to me since my periods don't normally go like that.

My period is now 4 days late. I took a pregnancy test and it was negative. Could i still be pregnant? Also I've had some weird symptoms that I normally don't have for periods. My breasts aren't sore but my nipples have been really sore. I'm extremely thirsty for water, and I'm cramping like I'm about to get my period and then nothing. When I go to the bathroom I have no spotting whatsoever but I have had some white discharge.

Could i be pregnant even though my ex said he didn't ejaculate inside me? How long should i wait before I take another pregnancy test?