Hi, I've been married for over a year now, and my husband has always used condoms since. My periods are regular (sometimes 2-3 days later than my period date max). I am 7 days late as of today, and I have been very hungry and extremely tired off-late. Mood swings are all over the place. I also have a slight dull pain in the lower left side of my abdomen, and also in my lower back. I took a pregnancy test this morning and the result came as a negative. Is there a possibility that I could be pregnant? If so, when should I take another test to make sure?