I was just breastfeeding my son and he fed really well on the right side for a bit and then pulled himself off. He then proceeded to latch back on and then shake his head back and forth tugging on my nipple until it popped back out of his mouth, then he would frantically look for it again and repeat. So I thought maybe something was wrong and I switched him to the left side. He fed for a while there too, then started doing it again. He would latch, bury his face in my breast and shake his head side to side tugging on my nipple. What the heck is he doing?