Welcome to HCM,
If you are having a normal cycle of 28 to 30 days it is the mid cycle period and the ovulation time and time of conceiving . So early is the period of fertilization if it is there ,it is unlikely that will give the symptoms of early pregnancy
For the symptoms you have mentioned , it may be some thing else .
May be you are having some anxiety
and having all these feelings. very early pregnancy may give rise to vomiting
tendency.To know whether you may be pregnant you will have to wait for few days more to miss a period and you go for urine test
It will be better to consult physician /gynecologist and get a check up .