I disagree with your avatar. Being able to hold the tears in when enduring pain means that the tears don't come from raw emotion, so the pain isn't bad enough. Try getting ripped apart, crushed, 1000 paper cuts, drowned, asphyxiated, getting eaten alive, having a heart attack and combusting all at once.
I think that may be slightly more painful then something like 'You failed the test you studied really hard for'. Which is the kind of thing you would smile to hold back tears for.
Oh wait. Your Usertitle. Nevermind then.