Baby wise philosophy

So I know Kaden is only 3 weeks, but I've been trying so
hard for the last week and 1/2 to establish his schedule.
I feel like I've done pretty good about getting him down
to a 2 1/2 to 3 hour schedule during the day, but then
like last night he finally fell asleep at 1, woke up at 4
then 6 then 7:30. I'm sitting with him now and he is
wide awake at 8:30. The night before last he went to
bed at 10:30, woke up at 1, 3, 5:30, 7:20! This can only
continue for a little bit longer before I go crazy. So, I'm
about to throw this baby wise nonsense out the window
and try something different, but I don't want to give up
too easily so I need some advice from you moms who
have done it and know what to do. Is he too little to let
him cry? He should at least be feeling full enough to last
3 hours at night, right? He is getting full feedings. He
may not be sucking as hard as he could be, but he's
got to be getting what he needs, well maybe not- who
knows at this point. It could be that I'm expecting too
much too soon. Just let me know would you?!!