Will past issues disqualify me?

I was thinking applying for a job that requires security clearance, but I have some past issues. The only red flags I could think of are the two times I ran away from home, one at 14 and one at 15. I admitted myself to a short-term (48 hours) psychiatric ward stay during one of these times. I’ve never used drugs or alcohol, been fired, or any of that stuff. My mental health is great now and I haven’t needed a therapist in about 7 years. Obviously I know it will impact me, but how terribly? How do I mitigate this?

Read the questions carefully, this may not even be covered due to your age and the passage of time.

I know a guy with a similar background but he was over 18 and he got cleared to work at one of the leading intel agencies. Mitigating factors in his case were the passage of time and solid work/school history since the incidents.