Sleepless mama needs help.

SOS. My 2 1/2 week old son won’t stay asleep when I lay him down. It wasn’t an issue until the past few days, but I’m on the verge of passing out from lack of sleep and need a solution. He falls asleep just fine while I’m holding him, and will stay asleep as long as I’m holding him, but as soon as I put him down, whether it’s in his bassinet, swing, bouncer, etc. He wakes up within 5 minutes and cries until I pick him back up. At which point he will fall back asleep. Help. Please. I beg you.