I experienced the same thing and relate 100% to the level of anxiety you are experiencing.
There is a lot of info out there about bedbugs and it can make even a healthy brain go crazy and experience real OCD feelings.
I just want to point out that the extreme treatments are more of a precaution. Your house is not infested with bugs if your exterminator only found one.
But with that, even big infestations are treatable. No one lives with bedbugs forever.
Please try to keep a healthy mindset. This will pass. I was so consumed with anxiety when I went through this and it was so unnecessary.
If you live in Brooklyn I can send you a number of a very kind and affordable exterminator.
Good luck!