hi, i havent had my menstrual cycle in a little over three months, last period was 01/22/2012 - 02/02/2012. took a few pregnancy test and 3 came out positive but 2 came out negative. i ve been having lower back pain , weight gain (extremely fast) dizzy spells now and then, nausea and abdominal cramping with sharp pain. i recently had a trans vaginal ultrasound and was told they did not see anything. so, im a little concerned about what i should do next.