Nexus 7(2012) hard bricked

Hello,
First time writing on the forum so please tell me if I do something wrong .So ,yesterday i've installed kubuntu on my nexus 7 , via platform tools (flashing img on fastboot).In kubuntu i have installed gpartition with terminal ,because i've saw that i only have 6 gig of free memory on 16 gig nexus 7 , and i wanted to know why.I opened it and when he finish analyze my tablet ,he find 15 gig of unalocatted space.So i decided to format that partition.After a minute he promted an error ,that he can't create disk label and adviced me to reboot before making any changes.After i closed all apps ,i rebooted my tablet , but something happened, she doesn't boot up any more.I tries diferent buttons combo,but she doesn't boot up,and i noticed that i can't access bootloader or custom recovery or fastboot.From some resources on internet i've found that it may be hard bricked.Can anyone tell me if is it hard bricked( i hope not) and if is it , how to solve that? I also want to add that i don't know to use nvflash , and i've never maked blob file backup. Can anyone pls help me?