Don't doctors normally only call when something is bad? The doctor's phone number is on my caller ID. There was no message left. I am so nervous that something is wrong. How long does it take to get results back from the blood work they do? I am a nervous wreck.

Doctors call for many different reasons. (insurance issues, remind you of appointment, remind you of not to eat or drink anything before an appointment, call and see how you are doing, to update information or to give you information on certain pregnancy classes etc..)

Blood work is sent to a lab and usually takes about a week.

Call them first thing in the morning and see what they wanted. It isn't always bad when a doctor's office calls. Relax and be positive.

P.S. If it was an emergency they would have left a message.

They might have called your number accidentally and hung up when they realized their error.

Like Clare said, doctors call for all sorts of things.
If you're really worried, CALL THEM!

My doc always freaks me out when they call. Normally they call just to tell me my test results are back in and that everything is okay.

Try and relax and call them back to see why they called. If something is wrong, they will keep calling until they get you on the line.