"Womp, Womp, Wah" are sounds used for mimicking crying noises or to denote being a cry baby. "Womp, womp" may also sound like "“Wah, Wah". For instance, "Cry me a river, Womp, Womp"
Womp in text slang means: A word that can be found in dub-step tracks. The sound coming from low bass frequencies.