What Causes Delay In Periods With Period Like Symptoms?

Hi I am a biy worried. I went to see my doctor today and they didnt help me or provide a solution. Instead they told me to come back in afew days. My period is two weeks late. I am active but use condoms. I last had a period on 20th May but it wasnt heavy. I normally last for 5 days. I have done 4 tests the last being this morning - and all have been negative. I am getting period like symptoms, should I just wait?? I have been feeling sick and did vomit a few days ago ..I had diaorrea too. But both have stopped..not sure if it was a bug. pleasehelp