Can self-inflicted scars prevent you from being accepted in the army?

When I was in late middle school - early high school I did some cutting on my legs. I'm thinking of joining the Army Reserves and I hope this won't disqualify me. I have never been diagnosed with a mental disorder, but I was put into a facility for bad behavior (only three or four days, though). My question is, will the scars disqualify me? Can I use scar removal cream? And will the Army dig all the way back into my records to see that I was a bad kid at thirteen? Thanks.