New 13 week old maltese

Hi everyone okay long story. I got a puppy in early Jan that unfortunately passed due to parvo(please no advice about this as I have talked to my vet about everything) so my place is/was contaminated but I have disinfected it a few times. The breeder offered me a new puppy and I took her up on the offer and got him yesterday at 13 weeks old with his puppy injections. I love him and he is amazing. I do feel a bit overwhelmed, stressed and scared due to various reasons such as the parvo, me wanting to do the best for him and I am writing a big test on Tuesday for my postgraduate degree. I'd like to hear what people's experiences are with getting an older puppy with tips if possible. I'm also a bit worried as I don't feel he sleeps enough and he seems to have fomo. He is awake for about 2 hours at a time and doesnt sleep that long maby an hour-ish? Could it be the new place and everything or should I try to enforce nap time more? No crate training please