Pregnant and fainting?!

Not sure what is going on.
Woke up this morning to make breakfast for my kids, I started making it and suddenly felt extremely nauseas, then It felt like my body was going numb and everything was getting dark, I stumbled to the couch before I lost all feeling and everything went black, it was 8am when this happened and I didn't come to until 930am and I woke up completely drained and exhausted, it scared the crap out of me! I'm 16 weeks pregnant and this has never happened to me.