I had a concussion that led to me being hospitalized (10 years ago).Will I need a waiver to join the military?

When I was seven I fell off of a large boulder while I was messing around with my brothers (about 15 feet) and got a pretty bad concussion. I got rushed to the hospital, but all I had to do was spend some time in recovery (1 or 2 nights, I don't remember exactly). Would I need a medical waiver for this past injury to join, even though it was so long ago? I'm kind of worried because I heard that all of the branches have been cutting back on their waivers for new recruits. Thanks for any info.