I have MacBook Air late 2011 with encryption enabled the mac froze so I just shut it down by pressing the power button .But the when I tried booting the gray screen appeared nothing else

I have MacBook Air late 2011 with encryption enabled the mac froze and I pressed the power button to shut it down but then the gray screen appeared no wheels nothing just gray. I tried all steps but nothing helped. Worse than that only the pram key combination works I cant get the cmd-r or just alt or any combination to work??? Any suggestions would help. Thanks!

P.s. I am on mountain lion with ssd encryption enabled. The mac froze when the internet stopped the one from the cable (I use ethernet usb one) when I turned wifi on it froze. I have disconnected everything when trying the steps except power cable.