Flashing A/C light

K so i turn on my a/c and it was blowing could air like normal well realize it starts to fill like regular outside air look down and a/c light is blinking so i turn off and on blows cold air and stops again with flashing light. get home for 20 mins go fill up with gas turn on again and it works perfect. i dont know if it is because i havent used it on the freeway again that maybe freeway speed has to do with it. Can anyone help???
I called the dealership and they said it needs serviced so i asked them what this service would be and he says he doesnt know maybe recharged. guessing just bull shit.

 

i will take a look at it thank you for the response i will post how it looks

 

My moms 03 Camry did the same thing, it ended up being a relay switch. GL!