A sleep test is an excellant idea. I, too, suffer from apnea and the CPAP made a huge difference. Sometimes I go through a bad patch and have tried melatonin, and although it worked it also resulted in serious diarrhia so quit that. I take a prescribed medication that has my restless legs under control and on a bad night there is good old benadryl. I also take valerian (it really stinks) with the restless leg stuff and do quite well. BUT see a sleep specialist first.
Exercise every day even if it's just a walk. Restrict napping to no more than 30 minutes a day and try a warm bath or shower just before going to bed. That always makes me a bit dopey.