How much longer?

When Lisa asked him if he'd switch bodies with her so she could see what it was like, surfing as a guy, Jack thought she was crazy. Now he's wondering where she went and starting to get worried about getting stuck in her weak girly body over night. If he'd known she could actually make them swap bodies, he'd never have said yes.  He only agreed because he thought it would help him get into her pants.  I guess maybe he got what he wanted, in a way, but he sure isn't happy about it!