.5-1 mg a day is a pretty low dose, so you probably wouldn't feel the more intense side effects. You may be especially sensitive to medications.
Clonazepam being a benzodiazepine can make people tired but ideally relaxed for anxiety disorders. Initially you may feel tired but as the benzos. are notorious for; Tolerance can build quickly. That is why most pdocs only use them prn or for a very short duration as tolerance and addiction issues are very common. 4 mg of klonopin is usually the ceiling, when prescribed and is usually only used for severe social anxiety and agoraphobia. Though with the most severe of the anxiety spectrum's doses may be higher for true agoraphobics. To answer the question, your brain will adapt and the tiredness will subside. Just be careful with the benzos. as withdrawal can be brutal.. If you are on a moderate amount daily. If it is not done correctly, ie. slowly reducing the dose and the amount you are on!

As for the original thread, 5 mg is usually never Rx'ed unless it is severe agor. Unless you have been on benzos. for a long time and developed tolerance. Then, yeah 5 mgs of Clonazepam will probably knock you out. I don't see why a pdoc or doc would prescribe you such a large dose? That would be verging on malpractice . I assume you just took the amount you chose!