There are a few telltale body language signs that say what is going on. Cutting past the political posturing, it seems there may be a bit of an outbreak of stained underwear in high places in Iran.
For Iran to lash out at the US strongly suggest things are not going well in Iran. This was never expected by the government, but because of the intense motivation of the opposition, it strongly shows what the government media censors have been trying to hide over the years. It also shows the government may have been believing its own propaganda.
The reaction is that of a cornered animal. There is no other comparison. If the comment is addressed at the US government asking Twitter to hold off on maintenance so the Iranian protesters could better communicate, it becomes even more obvious that there is panic in the Iranian government.
It is uncertain if it is fear of the world looking on, or fear of the protesters getting the upper hand. It is likely a bit of both as it tends to stop the Iranian government from getting like the Chinese did in the Tiananmen Square protests of 1989.
It is obvious to see the US and much of the world would like to see a change of power in Iran because of their nuclear weapons goals, of that there is no state secret. So to take sides passively with the team that was cheated out of victory is nothing new for the US. So with that thought, the Iranian government should know better than to bark at the US as it may only show the world the US is right in the eyes of the world as well as the eyes of the Iranian people.