Congrats on the baby Quaker! I got my Lita when she was 12 weeks old, and she turned 2 years old 2 months ago, and she's such a wonderful little clown bird...
Your Quaker will be just fine, it hasn't even been 24 hours since he got to his new home, so he just needs to settle in. I wouldn't "give him space" or "leave him alone", I hate that advice, I've heard that around over the years from people, that you should not interact with a new bird for days or weeks after bringing it home...that's just not true...While you certainly do not want to force him to do anything he doesn't want to do, that's not good, you also do not just want to not interact with him.
Where do you have his cage located in your home? If you don't have his cage located in the "main room" of your house, the room of your house where you and others spend most of their time when they are home (usually the living room, family room, TV room, den, etc.), then you definitely want to move it into that room, for a number of reasons. First of all, you don't want him to be in a back room/spare bedroom, etc. where he will be able to hear people are home but not see them...this usually results in a lot of screaming, and as you are going to find out, if you haven't already, Quakers scream quite a bit anyway, and loudly. Secondly, birds are much more likely to happily entertain themselves inside of their cages or on their play-stands with their toys if they are simply in the same room as their people are, even if they're not directly interacting with them...So if you're simply watching TV, reading a book, playing video games, talking, on the computer, etc., you want him in the same room as you, and this brings them a sense of comfort and happiness, as they can see you, they know where you're at, and then they usually will have a great time playing with their toys inside of their cages. And whenever you or others walk by his cage, be sure to talk to him softly/gently....Having his cage or his play-stand located in whatever room you guys spend most of your time will especially help him right now, as he is trying to get settled-in, as he needs to at the very least be "around" and in the presence of his people, so he can get used to you/them. And I hope you have a ton of different toys inside of his cage, because Quakers love to use their beaks to chew/play/destroy, and they are extremely intelligent, so they cannot be allowed to become bored, which happens very easily. So figure on having between 6-10 toys inside of his cage at all times (I hope you got him a pretty large cage), and you should rotate new toys in at least once every month so he doesn't become bored with them...And having a light, easily movable T-Stand or play-stand with some toys hanging from it, one that you can easily move from room to room so that he can be playing in whatever room you're in doing whatever you're doing is a really good idea. You can make a T-Stand out of 3/4" PVC pipe and fittings from Lowes (they have tons more than Home Depot, and are also much cheaper) for less than $10 if you have a hand-held PVC pipe cutter ($10 at Lowes too, get the cheapest one they have, works great). Then if you have an electric or hand-crank drill, you can attach metal S-hooks on the T-Stand to hang toys from. I have a ton of these that I have made, one in each room, so that wherever I'm at the birds can be in the same room and occupy themselves. And for right now, if you do have his cage located in the room of your house "where the action is" and where you guys spend your time, while you're watching TV or doing whatever today, I'd simply open up his cage door and let him come-out on his own, which he most-likely will once he realizes that you're in the room with him. He just needs to become accustom to being around his new people, and obviously "leaving him alone" isn't going to help...
Also, Quakers do that "no" head-shake all the time, that's where the name "Quaker" comes from, they shake their heads "no" and most also make that very distinct, Quaker sound...
