Sounds a bit weak, honestly.

16 K is, typically, the minimum required Hp for Thordan, and Thordan requires a lot of memorization for the mechanics and when to use which buffs at which time. So, having some extra padding while you're still learning the fight is probably a good idea. Personally, I ran Thordan with 18 or 19 K health until I got comfortable with the mechanics. I started to push more Str when I got more comfortable with the timing of the mechanics, but even now I rock 17 K. Pld dps does not see high burst returns like War and Drk, so the str you sacrifice for the extra 10k isn't going to make or break anything.

It does sound like you're a bit under-geared though. What weapons are you using at the moment?