The injections are not as bad as our minds make them out to be... TRUST ME
I had the same problem hehe...I've now had about 8 total plus a discogram which hurt like crazy but that's a whole diff. ballpark.
All you feel is pressure and they give you some local anestesia... there is no real pain with it(at least mine).
You just have to give it a shot because for some people it really makes the difference in pain. Convince yourself that you won't get hurt or anything and just go for it

It's worth a shot!
Hope the best for ya... let us know how it goes.