No, if you purchased an original psjailbreak, you purchased an outdated, un-updateable, over-priced peice of junk. Sorry...
They, made a lot of claims, and fulfilled very few of them. Look for psjailbreak threads.
STOP! Before you ask questions... READ the first post! RTFFP = Read The F*cking First Post
Yes, A 3.55 "jb" (cfw) is available, no >3.55 "jb" or cfw yet.
Yes, A 3.55 downgrade is available. But not to lower than stock firmware! (What it came with)
No >3.55 downgrade is out there yet.