01/31/2012 at 12:00 PM EST
promises she had an amazing 31st birthday – even though she spent part of it weeping.
The star's fiancé
, Dax Shepard, surprised her with a sloth at the couple's home, but before Bell could even meet the creature, she somehow sensed its presence.
"I immediately was overcome and thought, 'There's a sloth near,'" she told Ellen DeGeneres
on Tuesday's episode of her talk show. "And I didn't know how to process that because my entire life had been waiting for this moment, where I would get to interact with a sloth."
"I don't know how to compete with all this emotion," she said, "so I just kind of crawl up on the bed and I'm crying so hard."
Luckily, Shepard was recording Bell's reaction, which the actress shared during her interview. After learning that the sloth was staying for the day, a hysterical Bell asks in the video, "He's coming for the party?"