However, that looks bad and ugly due to the 0 being there, and also the max 16 character limit, so you can't make 20 characters that each represent 1 health point.
Nope, I mean this
IIIIIIIII - each bar representing half a heart.
Like this:
http://c.oppy.me/xDGEeq4H.png
Displaying the health as a number isn't really the problem here, I meant to have a health bar like this displaying under the player
Yes, it was hardcoded to 16 characters because that was the max playername you could get for a minecraft account, however with the custom names that limit was extended to 64 characters for custom names on anything other then players.