No, it is not normal, most likely you got your quest marked as Failed, make sure he does not die.
You can read a walkthrough guide on the first post of the map thread about Thun'Tharok Quest, it tells what items you should be having by now and what are the main tactics in dealing with the enemies.
Most likely you will not be able to kill the Box, because the key is to burst it down and to gain the needed burst power you need to finish Thun'Tharok quest. After it you will be able to improve your fire power.
As for the blossoms, you will need them in Act 3, and the last blossoms are located in Act 3.