Is it possible to still get a period (very light, lasted 3 days apprx) even if you are pregnant?. Are there some women who are pregnant for like 5 months who do not know about it? Is that possible? Also what are other possible causes of VERY light periods? (increasing each month to be lighter and lightter, and shorter) :( PS I am only 18 and began to get my period at 12 or maybe younger... it has always been fairly regular