What is wrong with my trigger?
All I did was change 

SET bounty:=(SELECT `Bounty` FROM `Questions` WHERE `QuestionID` = 
NEW.`QuestionID`); 


to 

SELECT `Bounty` INTO bountyvar FROM `Questions` WHERE `QuestionID` = NEW.`QuestionID`; 


and it started working... Why though xD 

Some light can be shed on that from this question: apparently some versions of MySQL just don't like some variations of syntax. Oh well. I'm glad this is over. I'm tired.