Here's hoping everything turns out fine!
Regarding the lack of energy, etc. - sometimes a bad cold will just do that to you. Also, while most guys do ok after an orchiectomy, sometimes the remaining testicle just gives out after a while and can't keep up. If everything comes back clear and the lack of energy and tiredness persist, it wouldn't be a terrible idea to consult an endocrinologist to get his hormone levels checked out.