My max heath is 12k

Looks like it is 13,625 in the picture.

Regardless, in 1 level your stats are going to change (usually for the worse). This is due to the game scaling your battle level. I know the article is out-dated but this should give you a good idea of what it means: http://esoacademy.com/faq/what-is-battle-level/

On a side note, I would change a couple things:

-Your mundus stone from the Ritual to something more magicka centered (i.e. Apprentice, Mage, etc.). Here are the mundus stones available: http://elderscrollsonline.wiki.fextralife.com/Mundus+Stones

-Your bow to a destruction staff. I don't know what you have on your back bar, but for more survivability you could use a restoration staff.

-You could also put 2 pieces of heavy equipment on IF you want more health and resistances but this is really not necessary if you keep shields up.
*Shields are important for Sorcerers - you have access to a class shield called Conjured Ward (http://www.esohead.com/skills/28418-conjured-ward) or you can use the light armor shield called Annulment (http://www.esohead.com/skills/29338-annulment).

Good luck.

Wards and surge with aoes should keep you alive. Dps will heal you, as will slotting a pet and the corresponding passives.

Juggernaut in heavy armor plus 2 pieces heavy will as well

Run 511, make sure your armor is at your level, don't use stamina skills. A sorcerer's suitability is related to their dps generally. I have 17.5k health on mine and about 43k mag.