well if it is just the qmobile inifinity then you might be SOL.
let this be a lesson learned. one of the most important tool a rooted phone should have is a custom recovery. once you have a recovery, the very first thing you need to do is make a nandroid backup. this a a complete backup of your phone. this is needed in cases like yours where if something goes wrong, you can just go back and restore a backup. there are other things you can do with recovery, but this is the most important.
also some other things to think about if when it comes to rooting:
1. for me having a developer community that supports your phone is a must. developer's are the ones who come up with ways to root your phone. they are the ones who develop custom roms and custom recoveries.
just remember no devs=no fun
2. check if there is custom roms for your device. custom roms are cool. developers take out all of the unnecessary bloatware. they usually optimize their roms to run a lot smoother.
3. if i want to get a device and i want to root it, i usually do my research first over at
xda developers forum if they have a section for your phone, that is a good sign. if they do not have a forum for your device....that usually means there is no dev community.
and like i said no devs=no fun.
4. and the very last thing is to do your research and plan for everything. look for guides to help you root. and once you found a guide that works for you then read, read, read, and then read some more.
i really wish i can help you out, but you picked a phone where is not much information out there. maybe see if you can get in touch with your provider and see if they can dig up a firmware you can use. if they do have one, keep in mind that it might unroot the phone.
good luck and keep us posted.