My boyfriend and I are afraid of going to far but...?

So my boyfriend and I are in our mid-teens. We make out/kiss. But recently we've been going farther than we intend to, we just get caught in the moment. Making out has escalated to touching above and below the waist, and more, etc. We don't really like PDA, but the more private places are also a problem b/c of the afore mentioned issue. Where should we draw the line?