Around in sickness or in health,
I come in complete and utter stealth.
Sports can create me,
While advil subside me.
I can come out with too much booze,
Or even without enough snooze.
Some say I happen when you get a bang,
At my worst, I can be described by this musical twang.
With me, age has no bounds
Cause when I hit you, your head pounds.
What am I?