It can be a complete abortion
where in all products of conception are emptied from uterus. The pregnancy
test will become normal as in your case. As it has stopped bleeding now, a normal cycle has to expected. Your symptoms such as nausea
are not on par with possibility of pregnancy. Please try to rule out other causes for nausea and gaseous distension. If you do not get period or if you get any bloody foul smelling discharge associated with fever or abdominal pain
, you surely need an ultra sonogram.