Vicki,
You are not over reactive but you really need to calm down and overcome your anxiety at this point. After all, your husband has got the best scenario with a clear report now. Close observation is still essential but too much worrying is not necessary.
Like Minnie, I never had a PET scan and for the follow up tests, I had CT scan, MRT, ultra-sound and chest X-ray.
By the way, Minnie, I sent you a private message several days ago, which you have not yet read.

Karen