Regarding stamina:
taken from:
http://eq.stratics.com/content/gamep..._faq.shtml#1.6
It's about warriors but each class has similars equation which change at different levels.
You gain a certain number of hit points per level (starting in the mid 20's and eventually rising as high as 40 per level for Ogres with max stamina). At 20 you gain approximately 2x what you received at 19th level. At 30 you receive approximately 2x what you received at 20th level, and at 40 you receive approximately 3x what you received at 20th level. There is also a large HP boost at level 53, and possibly more HP boosts. (More information on this will be forthcoming as the facts become available.)
In the 40's, your naked HP can be accurately determined with this formula: HP = Level * (27 + STA/11). Note that this formula is inaccurate at lower levels due to the rising number of HP gained per level. Warriors have the most hit points of any class.