These drugs aren't usually associated with that as much as some antidepressants are, but you are taking two drugs that work on the same neurotransmitter, GABA, and are both sedating. You also report sleep problems, and I have to say, taking a benzo for sleep is not a good idea. It's an addictive drug and interferes with REM sleep and over the long term will leave you with a benzo problem and rebound insomnia. And Neurontin is very sedating. Clonazepam targets GABA receptors; neurontin is GABA. It should be better for sleep than clonazepam, but people do react differently. Anything bugging you? Ever seen a therapist to see if your sleep problem can be fixed rather than medicated? Ever try something non-addictive and that doesn't interfere with REM sleep and doesn't cause rebound insomnia, such as melatonin or homeopathy?
Read the info they supplied with the drug or look at drugs.com.