I had an ultrasound yesterday. They checked my thyroids. It does not hurt at all and it is really easy. All you have to do is lay down and turn your head one way or another when they tell you to. First they put gel on you. Then they take the machine and put it on the gel. The machine is like an exray that goes through your skin but it sees the inside of your body not just bones. Sometimes I fall asleep like I did yesterday. So if you have to get an ultrasound don't be scared.