man...stop freaking out about what may or may not happen if you contribute to a project and just give it a try already...sheesh! you've already created this unreal mental image of how mean or whatever its gonna be but yet you are so paralyzed by your fear you wont even dip you toes to see how the reality compares to your fantasy.
your a (i think) grown person...life isnt always nice or fair thats what your family is for mostly. i truly believe you are much tougher then you think you are, and will be able to EASILY survive whatever words may or may not be thrown at you for forgetting to do exception checking (or whatever) in your chosen OSS project.
live a little...damn the torpedoes!