Bruised Ear??

My little guy is almost 7 months. I noticed on his ear tonight looks like he might have some bruises!? Do you think he could be pinching them that hard? He accidentally got knocked over while sitting today at daycare by another little one. Maybe from that? Anyone else notice this??? Also would you think I should ever take him to the Dr to get checked out after he was knocked over? He is acting normal, but just not sure? He worries me so much!