my period normally comes on the 22 but it came on the 19 and it only stayed on 3 days at first it was spottin then it was brown only a little red then brown again. ive been gaining weight and sleeping and eatin alot. been feeling like throwin up. and has had weird cravings like peanut butter and jelly sandwhiches dipped in tomato soup. and home pregnancy test came back negative. could i be pregant ?