Cramping. Is it normal?

So I'm a man but my wife is worried because she's 6 weeks along and has been having constant severe cramps and is worried about. This is our first pregnancy so we are both totally new to this. I've looked it up and even called the doctor to ask if this is normal and both said yes BUT I would like to hear similar experiences from other women out there. Do you feel cramps all the time too? No blood though.