Bedtime

My son will be 2 in January. He has been sleeping in his big boy bed (crib-to-daybed) for almost a year as he was climbing out of the crib. I have never had to fight him to sleep in his bed. Sometimes, if he wakes up in the middle of the night, he will crawl into bed with my hubby and myself. Since I am now 27+6 with our second baby, I have to sleep in the reclining chair in the living room as it is the only place I can get comfortable enough to rest. My son will snuggle with me in the chair until he falls asleep, like he always has, then I will go lay him down. For the last 3 nights or so, he will wake up a couple hours after I lay him down, come in the living room, and sit with me until he falls back asleep. I will lay him down again, only to be woke up a couple hours later again. Tonight, I decided to hold him for a little while longer than usual after he went to sleep and dozed off myself. I woke up a couple hours later and went to put him in his bed. He immediately woke up and wanted to go back to the chair. When I said no, he started crying. I tried patting/rubbing his back, talking to him, singing to him, even laying down beside him so he could cuddle while going to sleep. Nothing worked. He had a huge meltdown and almost made himself sick from crying so hard. Finally, I got him calmed down enough to talk to him and we went to the living room to try to go to sleep. He hasn't gone back to sleep yet. I am exhausted and at my wits end. I don't know what's causing him to hate sleeping in his big boy bed and only wanting to sleep with me in the chair.