Hello, i hit my head about 4 hours ago (stood on a rake, cartoon-like) and it smacked my head. it bled a little but stopped soon after, the actual bump hurt a bit, but stopped about 10 minutes after, i held ice on it. I didn't feel dizzy, tired, sick or anything. I felt and feel pretty normal. Now, could i have suffered concussion, and is it safe to sleep in a few hours?