K.M.
My first thoughts are to put him back in his crib, and consider how many naps he takes a day, and at what time. My 17 month old tosses and turns all night, but is still in a crib so it's fine. He's also starting to cut his eye teeth, and has lately been waking up crying a few times a night. As an example here's our "schedule". Elijah wakes up around 7-7:30, is ready (on his own) for a nap by 10:30 or 11. He usually sits in his crib and plays till he falls asleep and wakes up anytime between 12 and 2. Yes, sometimes he takes a very long nap. He only has that one nap, even though he starts getting tired around 6. Then by 8 he'll come to me and knod and I know he's ready for bed. He set this schedule himself, I just watch for the signs. So maybe your son is having too many naps during the day. Also sometimes not enough sleep during the day can cause restless nights. Is he warm enough at night? Is he too warm? Is he teething? This can all be reasons he won't sleep well. I hope I've said something that will help. Good luck.