This question is asking if my coup de grace manoeuvre action-sequence that could only be pulled off once per long rest is working as intended. I'll try to keep what I am trying to do as simple as possible; In this scenario, I am a level 5 sorcerer and level 2 paladin.

Round one; cast haste on self

Round two; try to hit target with longsword casting green flame blade, and expending a lv 3 spell slot for divine smite, then follow up with a second attack using my 2nd lv 3 level spell slot for a 2nd divine smite, but with my bonus action stop concentrating on haste, and cast thunderous smite as a bonus action, landing the hit for a total of: 1d8+2+4d8+1d6+1d8+2+4d8+2d6.

For the sake of this question, let's assume I have all of my spell slots unused.