Totally agree with Pax. Your tests were conclusively negative, and bed wetting isn't a symptom of an STD.
I'd also suggest a visit with his doctor, and would imagine that a prostate exam is a good idea.
You can let go of the anxiety of STDs now. :)
I would say he needs to see a doctor and get diagnosed if it's a big problem for him. You don't say how old he is, it could be the beginning of that old enlarged prostate starting to show it's ugly head, but who knows? Meaning, it really doesn't matter what you did, it was a relatively low risk activity, but you can't diagnose your husband on the internet. So again, if he has a health problem, he needs to see someone about it. Now. sometimes problems are so minor and doctors are so major that we just live with things, so that's your husband's call, but for you to worry about it out of guilt won't help him any, or you. Peace.