Is this normal?!?!

This is my 3rd pregnancy, first two ended in mc (3/12/12& 9/9/12) 1st time around 6 wks 2nd time at 8wks& 5 days! Im extremely worried and I know I should try to keep calm but I have no symptoms whatsoever compared to last time. I have no sore boobs nothing! Ive been vomiting lately& have had extreme diarrhea but I've also been diagnosed with the flu. I seen my obgyn this past thurs he said I was about 4 wks and go back back on the 8th for heartbeat I'm just wondering is it normal to not have any symptoms at all when with the first two I felt pregnant immediately???  I don't want to tell anyone yet for fear of what has happened before...help..