Has anyone else taken OTC sleep meds like Unisom, and had their legs start hurting and jerking?

Alter E, I used to work graveyard shift and I took Unisom about once a week when i really needed some good sleep. Most of the time it worked great, but for some reason it would occasionally give me the same symptoms you described and i would end up not getting any good sleep at all. My legs would be very very jumpy and achey/tingley. This seemed to happen more often after i had been taking it for a while.
To my knowledge it never did any serious damage. But if you are worried you should see your doctor.