Fixes health calculation system.

Fully fixes #96  
Closes #100  
Old system was a mess and horribly broken. This new system is much cleaner.
Also note: I left in debugging just so you can see @50Wliu 
Setting `parentheses=1`, then `break`ing out of the entire statement will bring the code down to `if(parentheses || health<=0)`, which will then produce an error.