Without actual proof, you can't really write it off as a bug. Saying you didn't change anything and actually proving it was identical are two very different things. If you can not prove something is a bug, then generally speaking the more plausible explaination is the correct one.
Odds of the system failing for you and not for the tens of thousands of others, unlikely. Odds of something specific you are doing different causing it, very likely.
While bugs do actually occur (so it is possible you really did encounter a bug), claiming something as a bug without proof is just a scapegoat.
"In anything, if you want to go from just a beginner to a pro, you need a montage." /w TankSpot WTB Montage for Raiders.