ugh!! I hate this! I hate hate hate bent cannulas!!! Sorry that you had to deal with this on your first time pumping!
You need to find the infusion set that is right for you! Which one are you using? I had two bent cannulas on the first two quick set infusion sets that I used. And I switched to Silhouette and it was much better. Other people complain about Silhouette. So it depends on your body and where you put the infusion set.
Ask the pump rep for samples of ALL the infusion sets. Including Sure-T, about which I have recently read some positive reviews. It has a fine metal needle. So you won't get bent cannulas. Users claim that it is painless, but try it out for yourself!