What Causes Dizziness, Headache And Weight Gain After Having Unprotected Sex?

Ok My last period was on the 9-13th of october and on the 28th oct my boyfriend and I had unprotected sex and my period was suppose to come on on the 9th of nov and still haven't. I have thrown up twice, bloating, gas, headaches, weight gain, dizziness, and fatigue but have not taken a test. I didn't see the need too because I did some research and it said you had to have sex within your ovulation cycle to get pregnant. so My question is should i take a test???