My 18 month old son has been so whiny and clingy for the past couple of days. Like he will throw a total hissy fit if I try to put him down. He wakes up and cries when he doesn't feel me by him and he just wants me to hold him all day, he barely plays by himself anymore. Baby #2 is due in 12 days, could he be sensing she is coming? Has anyone else experienced this?