What Causes Delayed Period And Stomach Bloating While UPT Is Negative?

I'm late for 28Days.. exactly a month.. I've checked 3 times and but still negative.. I've went to see a doctor 2 days back and its still negative.. But i'm having all the pregnancy symptoms.. Always feel nauseous but no vomitting.. Hate to see and talk to my people.. Elevate body temperature too.. My doctor advised me to wait for another 2 or 3 weeks more if still no menses, my doctor require me to come back for a check up.. Now my stomach is SOOoo bloated.. Feeling very uneasy.. I'm just so curious!!