If your periods are otherwise regular, you could either be pregnant or there may be some hormonal
upset, which can cause all the symptoms you are mentioning. My feeling is that you should get your periods shortly. Home pregnancy
tests are quite accurate, if done as per instructions.
However, if you are worried, there is no harm in seeing a doctor, who would repeat a pregnancy test, and if negative, give you medication to bring on your periods, if you so desired.