Not sure really it all depends on your gear, if you stripped naked then at a guess 2800 maybe
Just grind whatever you can 1 shot and wear a mixture of armour/protector, doing that not only makes you take less damage but you have more chance of getting a drop that you can wear as opposed to garment which can't be mixed, which also saves you time looking in stalls for stuff. Armour/protector gives you a 2 in 6 chance of being able to wear a drop while garment is only 1 in 6. You just wear whichever has the most phy defense, if you find a 47 pro chest you wear that until you find an armour one and so on.
I wore a mixture of whatever dropped until I got to 69 and then I got a garment, saved me loads of time.
You shouldn't die anyway unless your grinding orange monsters which there's no need to anyway, you'll level just as fast on whites or greens if not faster, depends what the spawns like.
In other words don't worry about your hp so much, it's normal.
