Does it really pass that fast?

I’m holding a sleeping 1 month old in my arms after a long fussy night. I feel so blessed and happy but also very tired. I’m trying to cherish every second cause everyone tells me newborn phase ends too fast. But I think it’s the hardest one and I kind of want it to end soon. I feel I’m torn between enjoying my tiny human and pure exhaustion. So does it really end that fast? Do you have any advice how to overcome exhaustion? What would you have told yourself if you could go back in time?