Pregnancy symptoms. Will be there?

My last period first day is aug 6 and I had 5 days periods on that cycle I had sex on aug 28 30 31 and one time I had unprotected sex not fully for few minutes from sep 2 monday night I got indigestion and I taken vomit 5 times Tuesday  morning before food I have vomit one time and little stomach on whole day again from Wednesday afternoon to till now I have loose motion today I had 5 times loose motion and i geting vomiting sensation frequently when I smell cooking and all and chance to be in pregnancy or food poision and sep 4 i got short breathness while walking more and talking and also sep 5  i taken urine pregnancy test it is negative and again night I got loose motion and after next day till past two days i  am normal i am not having any symptoms but i missed periods till now is  3 days if I want take pregnancy test on urine or beta hcg test when I want to take?? Please suggest when to take beta hcg test any chance of pregnancy is there??any chance of pregnancy will be there??