If you enter to it decided to make a good streak, you will definetely have a losing streak in just matter of minutes.
But yes, i remember when i had something like this, just like you are saying. I had 5 consecutive losses on the Casino Hold'em, it was crazy, but i lost five times in a row.
Most people do not understand that when it happens, it is the right time to leave the game.
Losing 5 times ina row isn't uncommon if the game is 50/50.
I don't know about the one you played though.
But let's say were playing a 50/50 game, well based on my calculations it means that there is a 1 in 32 chance you are going to lose 5 times ina row, which is actually quite high. I mean if you play for a while, chances are you are going to lose 5 times ina row almost certainly.