1) 머리를 좀 비어야 될 것 같아요.
2) 스트레스 좀 풀어야겠어요. / 스트레스 좀 풀고 싶어요.
Literally translated, it means:
1) I think I need to empty my head.
2) I need to relieve my stress. / I want to relieve my stress.
I tried to imagine how I would say it myself.
Hope this helps!