Not really sure what the question was; you were concerned about your safety to the patch at that level? How were you feeling, subjectively? I assume not near nod territory or you'd have told us so; tolerance wise I don't think you have a great deal to worry about. The combination of benzodiazepines, though, is potentially dangerous, especially if you add alcohol or other CNS depressants to the mix. Especially if this is your first time out with fentanyl, which is (or are a class of) opiates that are a chemically, pharmacologically, and subjectively a bit different from what you may be used to. You might very well wind up disappointed. I don't like fentanyl, personally. The problem and greatest risk of fentanyl is that the dose that we need to produce an equal amount of euphoria to something like hydromorphone or heroin is that, generally speaking, fentanyl will depress the respiratory system more.
This is all of course entirely subjective, but is a big factor in people overdosing on fentanyl-laced heroin (even when correctly dosed, people will keep doing it because they're not getting as high as they want to.) So I'd say a big no to combining other drugs with this and to take it carefully. You can take the patch off and wipe with cold water and soap and you will stop absorbing the drug reasonably rapidly, i.e. you're not going to put on the patch and go from zero to dying unless you have very low tolerance. The 50mcg/hr patch is equivalent to something like 30mg/day of oral Dilaudid, so you're not in that territory. If you don't add other drugs. That's when things get out of hand.
And yes, you can reuse the patch, although for a limited amount of time as they will dry up and although the drug will be there it will be more or less difficult to use depending on the type of patch. The best way to keep it for reuse relatively short term would be to reattach it to it's orginal packaging in a sealed zip lock bag. Time release mechanism can and will get wonky if it's exposed to extreme variances in environment, though, before reapplying it, but it is not a huge concern for you in all likelihood.
