What is the deal?

Today my son has been up for most of the day. He woke up around 5am and was up for an hour, I got my older kids ready for school and my baby to sleep but as soon as I lay him down he wakes. He was out fir maybe 30 mins. Then I had to go to the doctor he fell asleep in his car seat and slept a good bit. When he woke he refused to go back to sleep until hours later when I put him in his swing, he took about a 3 hour nap. He's been up now for 3 hours and every time I lay him down he wakes up. He's 2 weeks old and never had this problem before so I dunno what to do. I'm so tired I'm getting light headed and don't know what to do