As of Sunday morning, gas has risen (at the pump) 76 cents on average nationwide and over a dollar in places like San Diego

begin quote: 

 As of Sunday morning, the price of gas has risen 76 cents per gallon on average since the start of the war, according to GasBuddy, a sharp increase in a short amount of time. Wright said Americans should expect gas prices to come down in the next few weeks, but that there is no guarantee.

end partial quote from previous article. 

 Will we see gas prices of 10 to 20 dollars per gallon soon?

IT depends entirely on what Iran intends to do ongoing. I don't think you can believe anything the Iran Government says now because they are digging in for a "Forever War" against the U.S. and Western powers and they especially will do literally "ANYTHING" to assassinate Trump and members of his family now. This is a given knowing how things are done there. 

Iran militias right now are preparing for a Forever War or a Guerrila war much like the soldiers in Iraq did in Fighting American and NATO Forces in Iraq after Saddam was overthrown by Bush 2. 

The Iran Militias are a lot like ISIS in this respect. For them, this war will NEVER be over until Trump and the U.S. is gone.

And because the U.S. WON"T be gone this might never end now sort of like the war against the U.S. by ISIS.

So, it is very likely that the remnants of Iran's present Armies are becoming a new type of Shia ISIS right now.

HOwever, ISIS and Shia Terrorists (Iran) are killing each other every day now too because they are mortal enemies and have been since around 1000 AD. So, these two groups under different names have been already killing each other for over 1000 years already.