Jessica Simpson found out about her pregnancy while checking to make sure she could drink champagne during a romantic weekend away with her fiance and some friends.
The pop star-turned-businesswoman suspected she was with child and decided to make sure before heading off on a boozy break.
PHOTOS: Jessica's bump watch
She tells U.S. news show "Access Hollywood," "I was just kinda feeling a little off before we went away for a weekend... and I wanted to make sure I was in the clear to have a couple of glasses of champagne and I was not in the clear."
Simpson's fiance Eric Johnson, who was with her at the time, had no idea the singer was taking a pregnancy test in the bathroom and was "shocked" when she told him about the baby.
She adds, "I came in, like, shaking, like, 'Oh my gosh, oh my gosh, this is happening!' We both cried... We just sat there and stared at each other and were like, 'OK, we're doing this!'"
The star, who publicly confirmed rumors about her pregnancy at Halloween, Oct. 31, admits she is enjoying life as an expectant mum.
PHOTOS: Jess and Eric's ride to romance
She adds, "Pregnancy is a friend of mine, so everything has been running smoothly. So far so good, no morning sickness. I feel great. I'm tired but I'm making a baby."
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