Switched flights

I fly regularly , and book my flights online without a problem .
Recently I booked a Friday frenzy fare for myself and girlfriend from Mackay to brisbane from my iPhone , first of all it took 3 attempts because there site kept timing out.
4th attempt booked flights , we received a change of flight notice a week later on checking this I noticed the flights had reversed brisbane to Mackay rather then other way around , not sure if I was going crazy I asked around this had happened to another person we know .
I contacted the booking line in the Philippines by the sounds of it to be told it would be $750 to change our flights , original flights only cost us $290 return , so we were forced to lose our money and rebook with another carrier.
Has this happened to any one else ??Jetstar can go to hell