I would wait until you feel you've spent enough skill points on abilities and passives that you feel are enough to help. You always get a "battle spirit" buff in Cyrodiil, and I think anyone below veteran rank gets scaled to about level 50.
And don't forget to bring food that increases your maximum health. That's always helpful.

You could also try changing your playstyle a bit if you feel you die too much, a bit like me, I'm very squishy. Try using ranged attacks more often, like bows or staffs and spells. Know when to retreat and try to resist the temptation to chase a low health opponent if he runs too far from your group, you never know when he might lead you to his own group.