What do you mean "I shouldn't have"? Priiloader works on 3.4, although it is better to have it on 4.1 for hacks (unless you have the new version). It would be helpful if you provided more info, like:
Do you have bootmii, and is it boot2 or IOS?
Do you have a NAND backup?
What version of Priiloader do you have?
When did this brick happen (an install, an update, etc.)?
And any other info you can provide.
Btw, Priiloader will work with a GC controller, so hopefully you own or can buy one.