should I take a pregnancy test?

I have the IUD since Aug 2014 (paragard) and haven't had no problem. But for the past two weeks almost three, I been feeling tired and sleepy thought out the day, I been feeling sick when I smell food, I have been feeling nauseous but it come and go, but This week I been getting signs of my time of the month but it's coming to early. I been having unprotected sex since the IUD been put in. I had sex today after i been feeling bad cramps and I been spotting again and that never happened. What should I do?