user events and session_id

There's a session_id field returned with user events.

How do I know what "session" that correlates to?  For example, is it possible to identify that my app is making the changes, and thus I can ignore those events (because I'm the one who made them in the first place)?  Can I get the session_id of my "current session" (maybe based upon my current access token or something like that)?

Thanks in advance,

AJ