Hello Red,
ALtho my digonosis is different than yours I have had both SI injections and the epidurel injections... the SI injection was a bit painful to have done but I had more pain afterwards with that injection. The epidurel injection was much better didnt hurt as much going in and didnt hurt as much afterward either.
The first injection didnt do a thing for me and the second seemed to help for about 3 to 4 days and then pain was back...I go on Monday to get the 3rd injection so I will let you know how that one turns out.
It seems to me that you are in alot of pain already that these injections will be a breeze to what you are going trough now...also I got a shot before the injections that relaxes you and makes you tired so that helps as well....I do agree that it isnt much more than a flu shot though and its over before you know it...just make certain to have a list of questions you would like to ask before you go in so you dont forget them as you are nervious.
Good luck Red and I wish you well and hope they work for you...altho for many on here the injections havent worked so much there are many that they have worked for.
Take care and good luck
Lara