6 is ridiculous!

Well last night was night #6 in his toddler bed and it was by far the WORST night we have had since starting the whole thing. It feels like we took one step forward to take ten steps back. Mike put Wyatt to bed and everything should have gone well. We spent plenty of time outside playing and getting all that energy out, took a bath and then watched Blue's Clues before heading to bed fifteen-minutes later than usual. He should be knocked out for the night! Well at 1:35am we were woken up and I get up and put him back to bed. I've been sitting with him and rubbing his back or just being a presence in his room. Well after forty-minutes I head back to bed, only to be woken back up several short minutes later to a screaming baby. Again we go back to bed and do the same except I leave earlier and the crying starts again. This time I tell Mike that he's just going to have to cry a little bit. Then Mike gets up with him and puts him down, cries again. I get up with him a couple more times, cries again. Finally at 4:00am Mike gets up with him one last time and rocks him to sleep and then there was silence.
I'm at a total loss of what to do to help this. Do we let him cry? Do we keep putting him back in his bed and then leaving? Do we put him back to bed and then stay with him until he falls asleep? Either way I have no idea what to do or not to do and we are very tired.