This morning, LO had his first real "incident" where my heart was in my throat. He wound pulling a light cardboard box with a toy in it (about 2.5 feet tall) onto himself and hitting his head on the hardwood floor. I know he wasn't hurt by the weight of the box, but the back of his head hit the ground pretty hard.

He cried for about 2 minutes and then went right back to his normal self. My parents were here along with my husband and me and no one was overly concerned, saying that they thought he was fine.

I don't know, I just worry. I worry if something happened that we can't see/tell yet. He has been ok the rest of the day (a bit fussier at bedtime) but all in all, just like himself. I am annoyed with myself for letting him play near the box and for not running over fast enough to stop it from happening.

Is there anything that I should still be looking out for, symptom-wise?