What Causes Spotting, Stomach Bloating, Flatulence, Abdominal Cramps And Backache After Menstruation?

Hi, I had spotting on the ninth day after menustration later to which, I started getting bloated stomach with gas, occasional cramps in the lower abdomen, backache, feels like puking out and sometimes giddyness too. I am in the third week after my monthly cycle. I dont understand whether to go to doctor or still hang on for some more time till my expected period date. Please guide.