I think we were typing at the same time. :)
The only thing you can do with a child that young is be consistent. You giving in and letting him fall asleep somewhere other than his bed shows him that if he continues long enough, he will get what he wants. I know it's tiring, but it's the only way he will get the message.
7 o'clock is probably too early for him to go to bed.
Parenting is certainly exhausting. I really believe one of the biggest sacrifices you give up as a parent, consistently, is sleep. About the time all the kids are sleeping well and consistently the oldest ones become teenagers then you are back to not sleeping. ;D