Bié tài déyìyángyáng, xià cì kěnéng jiù bù yīyàng le.
Don't be so smug — next time might be different.
Tips
usage
得意扬扬 often carries a mildly negative connotation — it implies someone is overly proud or showing off. The variant 得意洋洋 (déyìyángyáng) uses 洋 instead of 扬 and is equally common.
grammar
Used as an adverbial with 地: 得意扬扬地 + verb. Also used as a predicate: 他很得意扬扬 (less common, 他得意扬扬的 is more natural).