Where should I go after defeating The Rotten?

Hi,

Well, it took me 3 hours but I finally managed to kill the fucking rotten, after that I took the portal there and opened the giant door and got evantually to Dragon's Sanctum and I am getting my ass destroyed there.

Wasted 3 humanity already but I just can't get pass.

So... I think that's maybe too early to go there. So where should I go now? I am level 98. Dex melee build (using Draglic sword +3)

And btw, is this consider to be good weapon? it does a lot of damage but feels too slow and take too much stamina.