Could I be pregnant when I have missed a period?

My period are always like clockwork. I am 24 years old and have been trying for a little un for 6 months. this month my period is late and it is heading on to 2 weeks. I have had a slight spotting for a day but nothing else. Got cramps and feel light headed and am going to the toilet all the time and have white discharge. Am I pregnant?? Or is it another false alarm. Please advise... Should I test myself, people say wait tillyour exactly 2 weeks late to be sure, should I?