Oh, another thing I forgot to mention, you really should try enhancing/smelting your weapons. It gives them considerable power so that even the level 1 Cedar spear you are using should last you up until you can get a Ginko Spear (level 10) or even better an Ice Cedar Spear (lowest level one is I think LV 12). I know you can def find the latter doing runs at Chinji cave in Yamataikoku village.
The Ice Cedar Spear has a skill called Ice Blossom that has a slow windup and high SP cost, but deals great damage to a wide radius. That skill on an enhanced spear to 40+ can do some serious damage.
Another thing I meant to ask was how are you building your character? Are you going full Vit?