Leaving a 1 month old at dads for a week??

So I️ really don’t think my ex understands how babies work. We’re not together but he wants to see the baby obviously. So I’ve said once he’s born I’ll come over you can see him but I️ don’t feel comfortable leaving him over night FOR A WEEK until he’s able to sleep trough the night and is a little older like 4 months.

My ex is like no, I’ll have him for a week. That’s why you have formula and pump breast milk.

I’m sorry but does anyone else find anything wrong with this? Am I️ being crazy? I️ just don’t feel comfortable with that at such a young age, that’s way too long to be a part from my baby.