Paranoid About Bed Bugs

Even though it has been a week since our apartment was fumigated for bed bugs, I am still worried. Any bugs that walk over any surface of our place that has been sprayed will die instantly...for 21 days after the initial spray. But...

Just when I was starting to get a better sleep, we found another bug. This time though, it was in the toilet, dead. When we thought about how it got there, there was only one explanation. The fan is almost directly over the toilet. So we taped plastic around the vent for now. This doesn't mean we have them in our bedroom. In fact, I am sure we don't. But it still made me uncomfortable as I tried to sleep last night. So the problem hasn't been solved, they're still living somewhere in the building...and traveling.

I'd love it if there was a way we could ensure that our apartment was sealed off from all the others. But I don't think that's possible. I've read articles that say they even walk across the halls to other apartments. Ick. What an annoyance.