My 11 week old, woke up from nap this am, with mottled skin of both lower extremities. It blanched white when pressed. Skin is its usual warm to touch. He slept in a short onesie, and wrapped in sleep wrap. He is acting very well, nursing, and alert. Now back to sleep, on his back, in sleep sack. Should I be worried? I observed this 1 time yesterday, then it was gone.