Yes, it's been badly handled and the Thais should have realised that once the Cambodians first shot rockets and they landed, like the one that flattened the 7-11 and killed people, they should have hit back really hard and hit everything they wanted to, and fast.
Why? Firstly, once the first rocket lands then the clock is ticking before some self-righteous third party jumps in and starts doing the "calm down, calm down" stuff.
Secondly, if you hit them hard, as the Thai military are way stronger, they have the opportunity to show their military strength so that in the future neighbours will leave them alone or think twice about taking the p!ss.
Thailand could have taken out all Cambodia's beligerent assets fast and should have done so, then can shrug its shoulders and say "fine" when the UN/China/US ect. wade in and say "enough"... too slow Thailand.