Do something that 你 enjoy for a happiness lift,or the best thing to do would be to tackle whatever's making 你 stressed head on. If 你 leave a problem,it won't go away,it'll only get worse over time so it's best to solve it quickly before it makes 你 even 更多 stressed.
go for a walk, listen to music, have a long bath, write in your diary, watch a funny film, read,draw,go on a shopping spree,eat 浓情巧克力 lol..anything 你 enjoy doing.. :)